tm2613185-2_424b5 - none

TABLE OF CONTENTS

The information in this preliminary prospectus supplement is not complete and may be changed. A registration statement relating to these securities has been declared effective by the Securities and Exchange Commission. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell these securities, and we are not soliciting offers to buy these securities, in any state or other jurisdiction where the offer or sale is not permitted.

Filed Pursuant to Rule 424(b)(5)

Registration No. 333-289306

SUBJECT TO COMPLETION, DATED APRIL 30, 2026

PRELIMINARY PROSPECTUS SUPPLEMENT
(To Prospectus Dated August 18, 2025)

$80 million

Common Stock
Pre-Funded Warrants to Purchase
Shares of Common Stock

We are offering shares of our common stock, par value $0.001 per share and, in lieu of offering shares of our common stock to certain investors, pre-funded warrants to purchase up to shares of common stock, pursuant to this prospectus supplement and accompanying prospectus. The purchase price of each pre-funded warrant is the price per share at which shares of common stock are being sold in this offering, minus $0.001, which is the exercise price of each pre-funded warrant. This prospectus supplement also relates to the offering of the shares of common stock issuable upon the exercise of such pre-funded warrants.

Our common stock is listed on the Nasdaq Global Select Market under the symbol “SENS.” The last reported sale price of our common stock on the Nasdaq Global Select Market on April 29, 2026 was $6.43 per share. There is no established public trading market for the pre-funded warrants, and we do not expect a market to develop. In addition, we do not intend to apply for a listing of the pre-funded warrants on the Nasdaq Global Select Market, any other national securities exchange or any other nationally recognized trading system.

We are a “smaller reporting company” under applicable Securities and Exchange Commission (“SEC”) rules and are subject to reduced public company reporting requirements. See “Prospectus Supplement Summary — Implications of Being a Smaller Reporting Company.”

Investing in our common stock involves a high degree of risk. You should read this entire prospectus supplement and the accompanying prospectus carefully. See “Risk factors” beginning on page S-6 and in the documents incorporated by reference into this prospectus supplement before investing in our common stock.

We have granted the underwriters an option to purchase additional shares of our common stock at the same price set forth above, within 30 days from the date of this prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

Per Share

Per Pre-Funded
Warrant

Total

Public offering price

Underwriting discounts and commissions(1)

Proceeds, before expenses, to Senseonics Holdings, Inc.

(1)

See “Underwriting” beginning on page S-21 of this prospectus supplement for additional information with respect to underwriting compensation.

The underwriters expect to deliver the shares of common stock against payment on or about , 2026.

Joint Book-Running Managers

TD Cowen

Barclays

Bookrunners

Mizuho

Lake Street

Prospectus Supplement dated , 2026

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS SUPPLEMENT

This document is part of a “shelf” registration statement on Form S-3 (File No. 333-289306) that we filed with the SEC on August 6, 2025, which was declared effective by the SEC on August 18, 2025. This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of this offering of common stock and adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference herein. The second part, the accompanying prospectus, provides more general information, some of which may not apply to this offering. Generally, when we refer to this prospectus, we are referring to both parts of this document combined. To the extent there is a conflict between the information contained in this prospectus supplement and the information contained in the accompanying prospectus or any document incorporated by reference therein filed prior to the date of this prospectus supplement, you should rely on the information in this prospectus supplement; provided that if any statement in one of these documents is inconsistent with a statement in another document having a later date — for example, a document incorporated by reference in the accompanying prospectus — the statement in the document having the later date modifies or supersedes the earlier statement.

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference herein were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

We have not, and the underwriters have not, authorized anyone to provide any information other than that contained or incorporated by reference in this prospectus supplement, the accompanying prospectus or in any free writing prospectus prepared by or on behalf of us or to which we have referred you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. This prospectus supplement and the accompanying prospectus do not constitute an offer to sell, or a solicitation of an offer to purchase, the securities offered by this prospectus supplement and the accompanying prospectus in any jurisdiction to or from any person to whom or from whom it is unlawful to make such offer or solicitation of an offer in such jurisdiction. The information contained in this prospectus supplement or the accompanying prospectus, or incorporated by reference herein or therein is accurate only as of the respective dates thereof, regardless of the time of delivery of this prospectus supplement and the accompanying prospectus or of any sale of our common stock. It is important for you to read and consider all information contained in this prospectus supplement and the accompanying prospectus, including the documents incorporated by reference herein and therein, in making your investment decision. You should also read and consider the information in the documents to which we have referred you in the sections entitled “Where You Can Find More Information” and “Incorporation of Certain Information by Reference” in this prospectus supplement and in the accompanying prospectus. You should not consider any information in this prospectus supplement or the accompanying prospectus to be investment, legal or tax advice. You should consult your own counsel, accountants and other advisers for legal, tax, business, financial and related advice regarding the purchase of the common stock offered by this prospectus supplement.

We are offering to sell, and seeking offers to buy, shares of our common stock only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement and the accompanying prospectus and the offering of the common stock in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement and the accompanying prospectus must inform themselves about, and observe any restrictions relating to, the offering of the common stock and the distribution of this prospectus supplement and the accompanying prospectus outside the United States. This prospectus supplement and the accompanying prospectus do not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement and the accompanying prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

Unless otherwise stated, all references in this prospectus supplement and the accompanying prospectus to “we,” “us,” “our,” “Senseonics,” “company” and similar designations refer, collectively, to Senseonics Holdings, Inc.

S-ii

TABLE OF CONTENTS

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus supplement, the accompanying prospectus and the information incorporated by reference herein and therein contain forward-looking statements that involve substantial risks and uncertainties. All statements, other than statements of historical fact, contained in this prospectus supplement, the accompanying prospectus and the information incorporated by reference herein and therein, including statements regarding our strategy, future operations, future financial position, future revenue, projected costs, prospects, plans and objectives of management, are forward-looking statements. The words “anticipate,” “believe,” “estimate,” “expect,” “intend,” “may,” “plan,” “predict,” “project,” “target,” “potential,” “will,” “would,” “could,” “should,” “continue,” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.

The forward-looking statements in this prospectus supplement, the accompanying prospectus and the information incorporated by reference herein and therein include, among other things, statements about:

•

the timing, progress and results of transition of commercial responsibility for Eversense back to the Company from Ascensia;

•

the timing of product launches;

•

the clinical utility of Eversense;

•

our ability to develop future generations of Eversense;

•

our ability to service our outstanding indebtedness;

•

the timing and availability of data from our clinical trials;

•

the timing of our planned regulatory filings and potential regulatory approvals and CE Certificates of Conformity;

•

our future development priorities;

•

our ability to obtain adequate reimbursement and third-party payor coverage for Eversense;

•

the purchasing patterns of our customers, including as a result of seasonality, which may be impacted by the timing and use of deductibles and out-of-pocket expense limits;

•

our expectations about the willingness of healthcare providers to recommend Eversense to people with diabetes;

•

our commercialization, marketing and manufacturing capabilities and strategy;

•

our ability to comply with applicable regulatory requirements;

•

our ability to maintain our intellectual property position;

•

our estimates regarding the size of, and future growth in, the market for continuous glucose monitoring systems;

•

our estimates regarding the period of time for which our current capital resources will be sufficient to fund our continued operations;

•

our estimates regarding our future expenses and needs for additional financing;

•

the anticipated levels of revenue, gross margin, gross profit net loss for the quarter ended March 31, 2026 and the anticipated levels of cash, cash equivalents, short-term investments and restricted cash and stockholders’ equity as of March 31, 2026; and

•

the proposed terms and conditions for an amendment (the “Second Amendment”) to the existing loan facility under a loan agreement (the “Loan and Security Agreement”) between the Company’s wholly-owned subsidiary Senseonics, Inc. and Hercules Capital, Inc. (together with its managed funds, “Hercules”), including the anticipated availability of additional loan commitments and the consummation of the transactions contemplated by the Second Amendment.

We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or

S-iii

TABLE OF CONTENTS

PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights selected information contained elsewhere in this prospectus supplement and the accompanying prospectus and in the documents we incorporate by reference. This summary does not contain all of the information you should consider before investing in our securities. You should read this entire prospectus supplement and the accompanying prospectus carefully, especially the risks of investing in our securities discussed under “Risk Factors” beginning on page S-6 of this prospectus supplement and under a similar heading in our Annual Report on Form 10-K for the year ended December 31, 2025, which is incorporated by reference in this prospectus supplement, along with our consolidated financial statements and notes to those consolidated financial statements and the other information incorporated by reference in this prospectus supplement and the accompanying prospectus, before making an investment decision.

Company Overview

We are a medical technology company focused on the design, development and commercialization of glucose monitoring products designed to transform lives in the global diabetes community with differentiated, long-term implantable glucose management technology. Our implantable CGM systems, including the Eversense E3 system (“Eversense E3”) and the Eversense 365 system (“Eversense 365” and, together with Eversense E3, “Eversense” or the “Eversense Systems”), are designed to continually and accurately measure glucose levels in people with diabetes via an under-the-skin sensor, a removable and rechargeable smart transmitter, and a convenient app for real-time diabetes monitoring and management for a period of up to six months in the case of Eversense E3 and up to twelve months in the case of Eversense 365, as compared to seven to 15 days for non-implantable CGM systems. In August 2020, we entered into a collaboration and commercialization agreement (“Existing Commercialization Agreement”), with Ascensia Diabetes Care Holdings AG (“Ascensia”) pursuant to which we granted Ascensia the exclusive right to distribute Eversense worldwide, with certain initial exceptions. In February 2022, Eversense E3, a 180 day CGM system, was approved by the FDA and Ascensia began commercializing Eversense E3 in the United States in the second quarter of 2022. In June 2022, we affixed the CE Mark to the extended life Eversense E3 system and Ascensia began commercialization in select markets in Europe during the third quarter of 2022. In September 2024, Eversense 365, a 365-day extended life CGM system, was approved by the FDA and Ascensia began commercializing Eversense 365 in the United States in the fourth quarter of 2024. In January 2026, we took over full commercial responsibility for Eversense 365 in the United States and began marketing and distributing the product with our own sales force. In January 2026, we also obtained CE Mark approval for Eversense 365 and are currently in the process of launching Eversense 365 in the European Territories.

On September 3, 2025 the Company and Ascensia signed a memorandum of understanding (“MOU”) related to the transfer of commercial operations relating to Eversense from Ascensia back to the Company. On December 31, 2025, the parties entered into the Master Asset Purchase Agreement formalizing this transfer and subsequently entered into A&R Commercialization Agreement, which terminated Ascensia’s right to market Eversense products in the U.S. and rendered Ascensia’s right to market Eversense products in Italy, Germany, Spain and Sweden (the “European Territories”) non-exclusive. Pursuant to the A&R Commercialization Agreement, effective January 1, 2026, we are entitled to 100% of the revenues derived from the sale of Eversense products in Italy, Germany, Spain and Sweden (the “European Territories”). As contemplated by the Master Asset Purchase Agreement, on March 12, 2026 we entered into local asset purchase agreements to facilitate the transition of Ascensia’s commercialization activities in the European Territories and we expect the closings of these transactions to occur on or before June 30, 2026, subject to customary regulatory and operational conditions.

Recent Developments

Preliminary Financial Results

Although we have not finalized our full financial results for the quarter ended March 31, 2026, we expect to report the following selected financial information as of and for the quarter ended March 31, 2026:

•

revenue of approximately $11.7 million;

S-1

TABLE OF CONTENTS

•

gross profit of approximately $6.4 million;

•

gross margin of approximately 54%;

•

net loss between $31 million and $33 million;

•

cash, cash equivalents, short-term investments and restricted cash of approximately $64.6 million; and

•

stockholders’ equity of between $33.7 million and $35.7 million.

The preliminary financial information presented above are estimates based on information available to management as of the date of this prospectus supplement, have not been reviewed or audited by our independent registered public accounting firm and are subject to change. We plan to announce our financial results for the quarter ended March 31, 2026 on May 7, 2026. Our actual reported financial results and financial condition as of and for the quarter ended March 31, 2026 may differ materially from the preliminary financial information presented in this prospectus supplement. The preliminary financial information presented in this prospectus supplement should not be viewed as a substitute for full financial statements prepared in accordance with generally accepted accounting principles in the United States and reviewed by our independent registered public accounting firm.

Hercules Debt Facility

We have entered into a non-binding term sheet with Hercules, the lender under our existing loan facility under the Loan and Security Agreement, setting forth the proposed terms and conditions of the Second Amendment. If consummated on the terms contemplated by the term sheet, the Second Amendment would increase the maximum borrowing capacity under our facility from $100.0 million to $140.0 million.

In addition to $35.0 million of borrowings currently outstanding under the existing facility, if effected in accordance with the term sheet, the amended facility would:

•

provide for $20.0 million of near-term loan commitments to be available, consisting of (i) a $10.0 million advance under a second tranche (“Tranche 2”) to be funded at the closing of the Second Amendment and (ii) a $10.0 million commitment under a third tranche (“Tranche 3A”) available at our option through September 15, 2026, subject to our satisfaction of a capital raising milestone, which we expect to satisfy through the net proceeds of this offering; and

•

provide for up to an additional $85.0 million future tranches of loan terms, subject to our satisfaction of certain terms and conditions and, with respect to the last $60.0 million uncommitted tranche, future lender investment committee approval.

After giving effect to the amended facility and the funding of Tranche 2 and Tranche 3A, as of December 31, 2025, our as adjusted total debt outstanding under the Loan and Security Agreement would have been approximately $55.0 million.

We currently anticipate that we will finalize and enter into the Second Amendment in early May 2026. However, the term sheet is non-binding and the Second Amendment of the loan facility is subject to the negotiation and execution of definitive legal documentation, formal approval by Hercules and the satisfaction or waiver of customary closing conditions.

Risks Associated with Our Business

Our business is subject to a number of risks of which you should be aware before making an investment decision. These risks are discussed more fully in the “Risk Factors” section of this prospectus supplement immediately following this prospectus supplement summary and in the “Risk Factors” section in our Annual Report on Form 10-K for the year ended December 31, 2025, which is incorporated by reference in this prospectus supplement.

Company Information

S-2

TABLE OF CONTENTS

commercialization of glucose monitoring systems to improve the lives of people with diabetes by enhancing their ability to manage their disease with relative ease and accuracy. From its inception in 1996 until 2010, Senseonics, Incorporated devoted substantially all of its resources to researching various sensor technologies and platforms. Beginning in 2010, the company narrowed its focus to designing, developing and refining a commercially viable glucose monitoring system.

In connection with the acquisition of Senseonics, Incorporated, we reincorporated in Delaware and changed our name to Senseonics Holdings, Inc. in 1996. Upon the closing of the acquisition, Senseonics, Incorporated merged with a wholly owned subsidiary of ours formed solely for that purpose and became our wholly owned subsidiary. Eon Care Services, LLC and Eon Management Services, LLC are wholly owned subsidiaries of Senseonics, Incorporated formed in April 2024 and July 2024, respectively. In November 2024, Eon Management Services, LLC entered into the Administrative Agreement with several professional corporations (“Eon Care PCs”), which are consolidated as variable interest entities (“VIEs”). The wholly owned entities and Eon Care PCs (collectively, “Eon Care”) were established to support patient access to the Eversense system by providing convenient Eversense insertion and training services. In connection with the transition of commercialization activities in Europe, the Company has established wholly owned subsidiaries in Italy, Germany, Spain and Sweden to support local commercial operations and distribution activities.

Our principal executive offices are located at 20451 Seneca Meadows Parkway, Germantown, Maryland 20876-7005 and our telephone number is (301) 515-7260. Our common stock is listed on the Nasdaq Global Select Market under the symbol “SENS.”

Available Information

Our internet website address is http://www.senseonics.com. The information contained on our website is not incorporated by reference into this prospectus, and you should not consider any information contained on, or that can be accessed through, our website as part of this prospectus or in deciding whether to purchase our securities.

Implications of Being a Smaller Reporting Company

We are a “smaller reporting company” as defined in Item 10(f)(1) of Regulation S-K. Smaller reporting companies may take advantage of certain reduced disclosure obligations, including, among other things, providing only two years of audited financial statements and reduced disclosure obligations regarding executive compensation. To the extent we take advantage of any reduced disclosure obligations, it may make the comparison of our financial statements with other public companies difficult or impossible.

S-3

TABLE OF CONTENTS

THE OFFERING

Common stock offered by Senseonics

shares of our common stock.

Pre-Funded Warrants Offered by Senseonics

pre-funded warrants to purchase shares of common stock. The purchase price of each pre-funded warrant is the price per share at which shares of our common stock are being sold in this offering, minus $0.001, which is the exercise price of each pre-funded warrant. Each pre-funded warrant will be exercisable from the date of issuance until the date the warrant is exercised in full. See “Description of Securities — Pre-Funded Warrants” for additional information. This prospectus supplement also relates to the shares of common stock issuable upon exercise of the pre-funded warrants.

Underwriters’ option to purchase additional shares of Senseonics’ common stock

The underwriters have the option to purchase additional shares of our common stock, which they may exercise, in whole or in part, for a period of 30 days from the date of this prospectus supplement.

Common stock to be outstanding immediately after this offering

shares of common stock or shares if the underwriters exercise their option to purchase additional shares of our common stock in full, assuming no exercise of any pre-funded warrants offered and sold by us.

Use of proceeds

We estimate that we will receive net proceeds from this offering of approximately $ (or approximately $ million if the underwriters’ option to purchase additional shares is exercised in full) from the issuance of our common stock in this offering, after deducting underwriting discounts and commissions and estimated offering expenses payable by us.

We currently intend to use the net proceeds of this offering to fund the ongoing launch of Eversense 365 and the continued development of pipeline products, as well as for working capital and general corporate purposes. See “Use of proceeds” on page S-10 of this prospectus supplement.

Risk factors

You should read the “Risk Factors” section of this prospectus supplement beginning on page S-6 and the “Risk Factors” section in our Annual Report on Form 10-K for the year ended December 31, 2025, which is incorporated by reference herein, for a discussion of factors to consider carefully before deciding to invest in shares of our common stock.

Nasdaq Global Select Market symbol

“SENS”

There is no established public trading market for the pre-funded warrants and we do not expect a market to develop. We do not intend to list the pre-funded warrants on the Nasdaq Global Select Market, any other national securities exchange or any other nationally recognized trading system.

S-4

TABLE OF CONTENTS

The number of shares of our common stock to be outstanding after this offering is based on 41,265,778 shares of our common stock issued and outstanding as of December 31, 2025, excluding:

•

2,364,911 shares of our common stock reserved for outstanding stock awards granted under our Amended and Restated 2015 Equity Incentive Plan;

•

1,539,625 shares of our common stock reserved for issuance under our Amended and Restated 2015 Equity Incentive Plan;

•

46,917 shares of our common stock reserved for outstanding stock awards granted under our Inducement Plan;

•

26,875 shares of our common stock reserved for issuance under our Inducement Plan;

•

1,404,389 shares of our common stock reserved for issuance under our 2016 Employee Stock Purchase Plan;

•

184,622 shares of our common stock reserved for outstanding stock awards granted under our 2023 Commercial Equity Plan;

•

315,378 shares of our common stock reserved for issuance under our 2023 Commercial Equity Plan; and

•

6,555,301 shares of our common stock reserved for issuance upon exercise of warrants.

Unless otherwise indicated, all information in this prospectus supplement assumes:

•

no exercise by the underwriters of their option to purchase up to additional shares of common stock in this offering;

•

no exercise of the pre-funded warrants that we are offering in this offering; and

•

no exercise of the outstanding options or warrants described above and no vesting and settlement of restricted stock units.

S-5

TABLE OF CONTENTS

RISK FACTORS

Investing in our securities involves a high degree of risk. Before you decide to invest in our securities, you should carefully consider the following risk factors and the risk factors discussed under the section titled “Risk Factors” contained in our Annual Report on Form 10-K for the year ended December 31, 2025 as may be updated by our subsequent filings, which are incorporated by reference into this prospectus supplement and accompanying prospectus in their entirety, together with all of the other information contained in this prospectus supplement and the accompanying prospectus or incorporated by reference into this prospectus supplement and the accompanying prospectus. The risks and uncertainties described in these documents are not the only ones we face. Other risks and uncertainties, including those that we do not currently consider material, may impair our business. If any of the risks discussed below or incorporated by reference actually occur, our business, financial condition, operating results or cash flows could be materially adversely affected. This could cause the value of our securities to decline, and you may lose all or part of your investment.

Risks Related to this Offering

Raising additional capital, including as a result of this offering, may cause dilution to our stockholders, restrict our operations or require us to relinquish rights to our product candidates.

Until such time, if ever, as we can generate substantial revenue, we expect to finance our cash needs through a combination of equity offerings, debt financings and license and development agreements. Other than our existing loan facility under the Loan and Security Agreement with Hercules, we do not currently have any committed external source of funds. To the extent that we raise additional capital through the sale of equity securities, including from this offering, or convertible debt securities, your ownership interest will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect your rights as a common stockholder. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends.

If we raise additional funds through collaborations, strategic alliances or marketing, distribution or licensing arrangements with third parties, we may be required to relinquish valuable rights to our research and development activities or product candidates on terms that may not be favorable to us. If we are unable to raise additional funds through equity or debt financings or other arrangements with third parties when needed, we may be required to delay, limit, reduce or terminate our product development or future commercialization efforts to third parties to develop and market product candidates that we would otherwise prefer to develop and market ourselves.

If you purchase shares of common stock or pre-funded warrants in this offering, you will suffer immediate dilution of your investment.

The price of our common stock in this offering may be substantially higher than the net tangible book value per share of our common stock. Therefore, if you purchase shares of our common stock or pre-funded warrants in this offering, you will pay a price per share that substantially exceeds our net tangible book value per share after this offering. Based on an offering price of $ per share, you will experience immediate dilution of $ per share, representing the difference between our as adjusted net tangible book value per share after giving effect to this offering and the offering price (but without giving effect to the exercise of the pre-funded warrants being offered in this offering). To the extent outstanding options or warrants are exercised, or shares of common stock are issued upon the vesting or other settlement of outstanding restricted stock units, you will incur further dilution. See the section titled “Dilution” below for a more detailed illustration of the dilution you would incur if you purchase shares of common stock in this offering.

We have broad discretion over the use of our cash and cash equivalents, including the net proceeds we receive in this offering, and despite our efforts may not use them in a manner that increases the value of your investment.

Our management has broad discretion to use our cash and cash equivalents, including the net proceeds we receive in this offering, to fund our operations and could spend these funds in ways that do not improve our results of operations or enhance the value of our common stock. The failure by our management to apply

S-6

TABLE OF CONTENTS

these funds effectively could result in financial losses that could have an adverse effect on our business, cause the price of our common stock to decline and delay the development of our product candidates and commercialization efforts for our products. Pending their use to fund operations, we may invest our cash and cash equivalents in a manner that does not produce income or that loses value.

A significant portion of our total outstanding shares are eligible to be sold into the market in the near future, which could cause the market price of our common stock to drop significantly, even if our business is doing well.

Sales of a substantial number of shares of our common stock in the public market, or the perception in the market that the holders of a large number of shares intend to sell shares, could reduce the market price of our common stock. Upon completion of this offering, shares held by our directors and officers will be subject to a contractual lock-up for a period of 90 days following the pricing date of this offering. These shares can be sold, subject to any applicable volume limitations under federal securities laws, after the earlier of the expiration of, or release from, the 90-day lock-up period. The balance of our outstanding shares of common stock, including any shares purchased in this offering, may be resold into the public market immediately without restriction, unless owned or purchased by our affiliates. Moreover, after this offering, some of the holders of our common stock will have the right, subject to specified conditions, to require us to file registration statements covering their shares or to include their shares in registration statements that we may file for ourselves or other stockholders.

All of our outstanding options and restricted stock units or shares that are otherwise issuable under our equity compensation plans are registered under the Securities Act of 1933, as amended (“Securities Act”), on a registration statement on Form S-8. These shares can be freely sold in the public market upon issuance, subject to volume limitations applicable to affiliates and the lock-up agreements described above, to the extent applicable.

We have not paid dividends in the past and do not expect to pay dividends in the future, and, as a result, any return on investment may be limited to the value of our stock.

We have never paid dividends and do not anticipate paying dividends in the foreseeable future. The payment of dividends will depend on our earnings, capital requirements, financial condition, prospects and other factors our board of directors may deem relevant. If we do not pay dividends, our stock may be less valuable because a return on your investment will only occur if our stock price appreciates and you sell our common stock thereafter.

If securities or industry analysts do not publish research or reports about our business, or if they issue adverse or misleading opinions regarding our stock, our stock price and trading volume could decline.

The trading market for our common stock will be influenced by the research and reports that industry or securities analysts publish about us or our business. If any of the analysts who cover us issue an adverse or misleading opinion regarding us, our business model, our intellectual property or our stock performance, or if our target studies and operating results fail to meet the expectations of analysts, our stock price would likely decline. If one or more of these analysts cease coverage of us or fail to publish reports on us regularly, we could lose visibility in the financial markets, which in turn could cause our stock price or trading volume to decline.

We may experience delays or difficulties in consummating the contemplated amendment to our loan facility under the Loan and Security Agreement with Hercules, and we cannot guarantee you that we will be able to amend the facility on the terms currently expected, on the timeline currently anticipated or at all.

We have entered into a non-binding term sheet with Hercules setting forth the proposed terms and conditions for an amendment to our existing loan facility under our Loan and Security Agreement with Hercules, which would expand the available borrowing capacity under the facility and provide additional immediate borrowing capability. We currently expect to finalize and close the amendment to the Hercules facility in early May 2026. However, the term sheet with Hercules is non-binding and the amendment of the loan facility is subject to the negotiation and execution of definitive legal documentation, formal approval by Hercules and the satisfaction or waiver of customary closing conditions.

S-7

TABLE OF CONTENTS

We may experience delays or difficulties in consummating the amendment to the loan facility, and there can be no assurance that the loan facility will be amended on the terms contemplated by the non-binding term sheet or at all. If we are unable to consummate the amendment to the loan facility on the terms contemplated by the non-binding term sheet, on the timeline that we anticipate or at all, we would not have access to the additional borrowing capacity that the amendment contemplates, and it could materially and adversely impact our future liquidity and our financial condition. It could also cause us to have to seek alternative sources of capital, which may not be available to us on acceptable terms, or at all. Furthermore, even if we enter into the Second Amendment, the amended Hercules facility is expected to include tranches that are subject to the achievement of specified revenue, gross margin, and capital-raising milestones and, with respect to certain tranches, future approval by Hercules’s investment committee. There can be no assurance that we will achieve the required milestones or that Hercules will approve these future tranches. Failure to achieve the applicable milestones or obtain investment committee approval with respect to any such tranche would limit our access to the additional capital we currently anticipate being available under the amended facility.

Our preliminary financial results as of and for the three months ended March 31, 2026 included in this prospectus supplement are based on information currently available to management and are subject to change.

The preliminary estimated financial results contained in “Prospectus Supplement Summary — Recent Developments — Preliminary Financial Results” represent only preliminary financial results and are based on our estimates and assumptions and information available to management as of the date of this prospectus supplement. We have not completed our financial closing procedures for the quarter ended March 31, 2026. Our actual financial results as of and for the three months March 31, 2026 are subject to the completion of our financial statements as of such date and such period. Our actual financial results as of and for the three months ended March 31, 2026 may materially differ from the preliminary estimated financial results we have provided as a result of, among other things, quarter-end closing procedures and/or adjustments, completion of our final adjustments and other operational procedures, review by our independent registered public accounting firm and other developments arising between now and the time that our financial results for such period are finalized.

The preliminary estimated financial information included in this prospectus supplement has been prepared by, and is the responsibility of, our management. Our independent registered public accounting firm, has not audited, reviewed, examined, compiled, nor applied agreed-upon procedures with respect to the preliminary financial information. Accordingly, our independent registered public accounting firm does not express an opinion or any other form of assurance with respect thereto. Complete results as of and for the three months ended March 31, 2026 will be included in our Quarterly Report on Form 10-Q for the period ended March 31, 2026. See the other risks described in this section and “Special Note Regarding Forward-Looking Statements” for additional information regarding factors that could result in differences between these preliminary and the actual financial results we will report as of and for the period ended March 31, 2026.

Risks Related to the Pre-Funded Warrants

There is no public market for the pre-funded warrants.

There is no established public trading market for the pre-funded warrants and we do not expect a market to develop. In addition, we do not intend to apply to list the pre-funded warrants on the Nasdaq Global Market Select, any other national securities exchange or any other nationally recognized trading system. Without an active market, the liquidity of the pre-funded warrants will be limited.

Holders of pre-funded warrants will have no rights as stockholders until they acquire shares of our common stock.

Until holders of pre-funded warrants acquire shares of our common stock upon exercise of their pre-funded warrants, and acquire shares of our common stock, such holders will have no rights with respect to the common stock underlying such pre-funded warrants, including any voting rights. Upon exercise of

S-8

TABLE OF CONTENTS

the pre-funded warrants, holders will be entitled to exercise the rights of a holder of shares of our common stock only as to matters for which the record date occurs after the exercise date.

Significant holders or beneficial owners of our common stock may not be permitted to exercise the pre-funded warrants that they hold.

A holder of the pre-funded warrants will not be entitled to exercise any portion of any pre-funded warrant that, upon giving effect to such exercise, would cause the aggregate number of our common stock beneficially owned by such holder (together with its affiliates) to exceed 9.99% (or, 61 days after a written notice from such holder, any other percentage not in excess of 19.99%) of the number of shares of our common stock immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the pre-funded warrants. As a result, a holder of the pre-funded warrants may not be able to exercise its pre-funded warrants for our common shares at a time financially beneficial for it to do so. See “Description of Securities — Pre-Funded Warrants” for additional information.

We will not receive significant additional funds upon the exercise of the pre-funded warrants being offered.

In certain limited circumstances, each pre-funded warrant may be exercised by way of a cashless exercise, meaning that the holder may not pay a cash purchase price upon exercise, but instead would receive upon such exercise the net number of shares of our common stock determined according to the formula set forth in the pre-funded warrant. Accordingly, we may not receive any additional funds upon the cashless exercise of the pre-funded warrant or if the pre-funded warrant altogether are not exercised at all. In addition, the pre-funded warrants have an exercise price of $0.001 per share of our common stock, and as a result we will not receive significant additional funds upon their exercise even if exercised for cash.

If we do not maintain a current and effective registration statement relating to the common stock issuable upon exercise of the pre-funded warrants, holders will only be able to exercise such pre-funded warrants on a “cashless basis.”

If we do not maintain a current and effective registration statement relating to the common stock issuable upon exercise of the pre-funded warrants at the time that holders wish to exercise such pre-funded warrants, they will only be able to exercise them on a “cashless basis” provided that an exemption from registration is available. As a result, the number of shares of common stock that holders will receive upon exercise of the pre-funded warrants will be fewer than it would have been had such holder exercised his warrant for cash, and holders may be limited in their ability to immediately sell shares upon exercise subject to volume or other securities law limitations. Further, if an exemption from registration is not available, holders would not be able to exercise on a cashless basis and would only be able to exercise their pre-funded warrants for cash if a current and effective registration statement relating to the common stock issuable upon exercise of the pre-funded warrants is available.

S-9

TABLE OF CONTENTS

USE OF PROCEEDS

We estimate that we will receive net proceeds of approximately $ million (or approximately $ million if the underwriters’ option to purchase additional shares is exercised in full) from the issuance of our common stock and pre-funded warrants in this offering after deducting underwriting discounts and commissions and estimated offering expenses payable by us.

We plan to use the net proceeds from this offering primarily to fund the ongoing launch of Eversense 365 and the continued development of pipeline products, as well as for working capital and general corporate purposes.

This expected use of our net proceeds from this offering represents our intentions based upon our current plans and business conditions, which could change in the future as our plans and business conditions evolve. Predicting the cost necessary to develop and market product candidates can be difficult, and therefore, the amounts and timing of our actual expenditures may vary significantly depending on numerous factors, including the progress of our product development, the status of and results from clinical trials, as well as any collaborations that we may enter into with third parties for our product development, and any unforeseen cash needs.

As a result, our management will retain broad discretion over the allocation of the net proceeds from this offering, and investors will be relying on the judgment of our management regarding the application of the net proceeds from this offering. The timing and amount of our actual expenditures will be based on many factors, including cash flows from operations and the anticipated growth of our business. Pending these uses, we expect to invest the net proceeds in short-term, interest bearing obligations, certificates of deposit or direct or guaranteed obligations of the United States. The goal with respect to the investment of these net proceeds is capital preservation and liquidity so that such funds are readily available to fund our operations.

S-10

TABLE OF CONTENTS

DILUTION

If you invest in our common stock or pre-funded warrants in this offering, your interest will be immediately diluted to the extent of the difference between the offering price per share and the as adjusted net tangible book value per share of our common stock immediately after this offering.

As of December 31, 2025, our net tangible book value was $55.7 million, or $1.35 per share of common stock. We calculate net tangible book value per share by dividing the net tangible book value, which is total assets less total liabilities, excluding right of use assets and other intangible assets by the number of outstanding shares of our common stock. Dilution with respect to net tangible book value per share represents the difference between the amount per share paid by purchasers of shares of common stock in this offering and the net tangible book value per share of our common stock immediately after this offering.

Our as adjusted net tangible book value as of December 31, 2025 was $ million, or $ per share of common stock. As adjusted net tangible book value per share represents the amount of our total assets less our total liabilities, excluding right of use assets and other intangible assets after giving effect to the sale and issuance of shares of our common stock, at a price of $ per share, and $ per pre-funded warrant, which equals the offering price per share of the common stock less the $0.001 per share exercise price of each such pre-funded warrant (and excluding shares of common stock issued upon exercise of the pre-funded warrants, any proceeds which may be received upon exercise of the pre-funded warrants, or any resulting accounting associated with the exercise of pre-funded warrants), net of estimated placement expenses payable by us. As adjusted net tangible book value per share represents as adjusted net tangible book value divided by the total number of shares of our common stock outstanding as of December 31, 2025.

After giving effect to the sale of shares of common stock in this offering, after deducting underwriting discounts and commissions and estimated offering expenses payable by us, at the public offering price of $ per share, our as adjusted net tangible book value as of December 31, 2025 would have been approximately $ million, or approximately $ per share. This represents an immediate increase in net tangible book value of $ per share to our existing stockholders and an immediate dilution of $ per share to investors participating in this offering.

The following table illustrates this dilution on a per share basis: The following table illustrates this per share dilution to the new investors purchasing shares of our common stock in this offering:

Public offering price per share			$
Net tangible book value per share as of December 31, 2025	$	1.35
As adjusted net tangible book value as of December 31, 2025
Increase in net tangible book value per share attributable to investors purchasing our common stock in this offering
As adjusted net tangible book value per share after giving effect to this offering
Dilution per share to new investors purchasing common stock in this offering			$

If the underwriters exercise their option to purchase additional shares of our common stock in full in this offering, the increase in the as adjusted net tangible book value per share to existing stockholders after this offering would be $ per share and the dilution to investors purchasing common stock in this offering would be $ per share.

The above discussion and table are based on 41,265,778 shares of our common stock outstanding as of December 31, 2025, excluding:

•

2,364,911 shares of our common stock reserved for outstanding stock awards granted under our Amended and Restated 2015 Equity Incentive Plan;

•

1,539,625 shares of our common stock reserved for issuance under our Amended and Restated 2015 Equity Incentive Plan;

•

46,917 shares of our common stock reserved for outstanding stock awards granted under our Inducement Plan;

S-12

TABLE OF CONTENTS

MATERIAL U.S. FEDERAL INCOME TAX CONSIDERATIONS TO NON-U.S. HOLDERS

The following summary describes the material U.S. federal income tax consequences of the acquisition, ownership and disposition of our common stock and Pre-Funded Warrants acquired in this offering by Non-U.S. Holders (as defined below). This discussion is not a complete analysis of all potential U.S. federal income tax consequences relating thereto, and does not address the potential application of the Medicare contribution tax on net investment income, the alternative minimum tax, or the special tax accounting rules under Section 451(b) of the Internal Revenue Code of 1986, as amended (the “Code”), and also does not address any U.S. federal non-income tax consequences, such as estate or gift tax consequences, or any tax consequences arising under any state, local or foreign tax laws. Special rules different from those described below may apply to certain Non-U.S. Holders that are subject to special treatment under the Code, such as financial institutions, insurance companies, tax-exempt organizations, governmental organizations, broker-dealers and traders in securities, certain former U.S. citizens or long-term residents, “controlled foreign corporations,” “passive foreign investment companies,” corporations that accumulate earnings to avoid U.S. federal income tax, persons deemed to sell our common stock or Pre-Funded Warrants under the constructive sale provisions of the Code, persons that hold our common stock or Pre-Funded Warrants as part of a “straddle,” “hedge,” “conversion transaction,” “synthetic security” or integrated investment or other risk reduction strategy, persons who acquire our common stock through the exercise of an option or otherwise as compensation, “qualified foreign pension funds” as defined in Section 897(l)(2) of the Code and entities all of the interests of which are held by qualified foreign pension funds, partnerships and other pass-through entities or arrangements, and investors in such pass-through entities or arrangements. Such Non-U.S. Holders are urged to consult their own tax advisors to determine the U.S. federal, state, local and other tax consequences that may be relevant to them. Furthermore, the discussion below is based upon the provisions of the Code, and Treasury regulations, rulings and judicial decisions thereunder as of the date hereof, and such authorities are subject to differing interpretations and may be repealed, revoked or modified, perhaps retroactively, so as to result in U.S. federal income tax consequences different from those discussed below. We have not requested a ruling from the U.S. Internal Revenue Service (the “IRS”) with respect to the statements made and the conclusions reached in the following summary, and there can be no assurance that the IRS will agree with such statements and conclusions. This discussion assumes that the Non-U.S. Holder holds our common stock and Pre-Funded Warrants as a “capital asset” within the meaning of Section 1221 of the Code (generally, property held for investment).

Persons considering the purchase of our common stock pursuant to this offering should consult their own tax advisors concerning the U.S. federal income, estate and other tax consequences of acquiring, owning and disposing of our common stock or Pre-Funded Warrants in light of their particular situations as well as any consequences arising under the laws of any other taxing jurisdiction, including any state, local or foreign tax consequences.

For the purposes of this discussion, a “Non-U.S. Holder” is a beneficial owner of common stock or Pre-Funded Warrants that is neither a “U.S. Holder,” nor a partnership (or other entity treated as a partnership for U.S. federal income tax purposes regardless of its place of organization or formation). A “U.S. Holder” means a beneficial owner of our common stock that is, for U.S. federal income tax purposes, any of the following:

•

an individual who is a citizen or resident of the United States; for U.S. federal income tax purposes (including any individual considered to be a U.S. resident for tax purposes under the “substantial presence” test within the meaning of Section 7701(b) of the Code);

•

a corporation (or other entity treated as a corporation for U.S. federal income tax purposes) created or organized in or under the laws of the United States, any state thereof or the District of Columbia;

•

an estate, the income of which is subject to U.S. federal income taxation regardless of its source; or

•

a trust if it (1) is subject to the primary supervision of a court within the United States and one or more “United States persons” (as defined in the Code) have the authority to control all substantial decisions of the trust or (2) has a valid election in effect under applicable Treasury regulations to be treated as a United States person.

If an entity or arrangement that is classified as a partnership for U.S. federal income tax purposes holds our common stock or Pre-Funded Warrants, the tax treatment of a person treated as a partner in

S-14

TABLE OF CONTENTS

such partnership for U.S. federal income tax purposes generally will depend on the status of the partner, the activities of the partner and the partnership and certain determinations made at the partner level. A person treated as a partner in a partnership or who holds our common stock through another pass-through entity should consult his, her or its own tax advisor regarding the tax consequences of the ownership and disposition of our common stock through a partnership or other pass-through entity, as applicable.

THIS DISCUSSION IS FOR INFORMATIONAL PURPOSES ONLY AND IS NOT TAX ADVICE. PROSPECTIVE INVESTORS SHOULD CONSULT THEIR TAX ADVISORS REGARDING THE PARTICULAR U.S. FEDERAL INCOME TAX CONSEQUENCES TO THEM OF ACQUIRING, OWNING AND DISPOSING OF OUR COMMON STOCK OR PRE-FUNDED WARRANTS, AS WELL AS ANY TAX CONSEQUENCES ARISING UNDER ANY STATE, LOCAL OR FOREIGN TAX LAWS AND ANY OTHER U.S. FEDERAL TAX LAWS OR UNDER ANY APPLICABLE INCOME TAX TREATY.

Treatment of Pre-Funded Warrants

Although it is not entirely free from doubt, we believe a pre-funded warrant should be treated as a share of our common stock for U.S. federal income tax purposes and a holder of pre-funded warrants should generally be taxed in the same manner as a holder of such shares, as described below. Accordingly, no gain or loss should be recognized upon the exercise of a pre-funded warrant and, upon exercise, the holding period of a pre-funded warrant should carry over to the share received. Similarly, the tax basis of the pre-funded warrant should carry over to the share received upon exercise, increased by the exercise price of $0.001 per share. If a pre-funded warrant expires without being exercised, the holder should recognize a capital loss in an amount equal to such holder’s tax basis in the pre-funded warrant. This loss will be long-term capital loss if, at the time of the expiration, the holder's holding period in the pre-funded warrant is more than one year. The deductibility of capital losses is subject to limitations.

Our characterization is not binding on the IRS, and the IRS may treat our pre-funded warrants as warrants to acquire our common stock. In that case, the amount and character of your gain with respect to an investment in our pre-funded warrants could be materially different than the discussion set forth below. Accordingly, each holder should consult his, her or its own tax advisor regarding the risks associated with the acquisition of prefunded warrants pursuant to this offering (including potential alternative characterizations). The balance of this discussion generally assumes that a pre-funded warrant is treated as a share of our common stock for U.S. federal income tax purposes, and references to common stock include pre-funded warrants.

Distributions and Constructive Distributions

As discussed under “Dividend Policy” above, we do not expect to make cash distributions to holders of our common stock in the foreseeable future. Distributions, if any, made on our common stock to a Non-U.S. Holder to the extent treated as made out of our current or accumulated earnings and profits (as determined under U.S. federal income tax principles) generally will constitute dividends for U.S. federal income tax purposes and will be subject to withholding tax at a 30% rate or such lower rate as may be specified by an applicable income tax treaty, subject to the discussions below regarding effectively connected income, backup withholding and foreign accounts. To obtain a reduced rate of withholding under a treaty, a Non-U.S. Holder generally will be required to provide us or our withholding agent with a properly executed IRS Form W-8BEN (in the case of individuals) or IRS Form W-8BEN-E (in the case of entities), or other appropriate form, including a U.S. taxpayer identification number, or in certain circumstances, a foreign tax identifying number, and certifying the Non-U.S. Holder’s entitlement to benefits under that treaty. This certification must be provided to us or our withholding agent prior to the payment of dividends and must be updated periodically. In the case of a Non-U.S. Holder that is an entity, Treasury regulations and the relevant tax treaty provide rules to determine whether, for purposes of determining the applicability of a tax treaty, dividends will be treated as paid to the entity or to those holding an interest in that entity. If a Non-U.S. Holder holds stock through a financial institution or other agent acting on the holder’s behalf, the holder will be required to provide appropriate documentation to such agent. The holder’s agent will then be required to provide certification to us or our withholding agent, either directly or through other intermediaries. If the Non-U.S. Holder is eligible for a reduced rate of U.S. federal withholding tax under

S-15

TABLE OF CONTENTS

an income tax treaty and the Non-U.S. Holder does not timely file the required certification, the Non-U.S. Holder may be able to obtain a refund or credit of any excess amounts withheld by timely filing an appropriate claim for a refund with the IRS.

We generally are not required to withhold U.S. federal tax on dividends paid to a Non-U.S. Holder that are effectively connected with the Non-U.S. Holder’s conduct of a trade or business within the United States (and, if required by an applicable income tax treaty, are attributable to a permanent establishment or fixed base that such holder maintains in the United States) if a properly executed IRS Form W-8ECI, stating that the dividends are so connected, is furnished to us or our withholding agent (or, if stock is held through a financial institution or other agent, to such agent) prior to the payment of such dividends. In general, such effectively connected dividends will be subject to U.S. federal income tax, on a net income basis at the regular rates applicable to United States persons. A corporate Non-U.S. Holder receiving effectively connected dividends may also be subject to an additional “branch profits tax,” which is imposed, under certain circumstances, at a rate of 30% (or such lower rate as may be specified by an applicable treaty) on the corporate Non-U.S. Holder’s effectively connected earnings and profits, subject to certain adjustments. Non-U.S. Holders should consult their tax advisors regarding any applicable income tax treaties that may provide for different rules.

To the extent distributions on our common stock, if any, exceed our current and accumulated earnings and profits, they will first reduce the Non-U.S. Holder’s adjusted basis in our common stock, but not below zero, and then will be treated as gain to the extent of any excess, and taxed in the same manner as gain realized from a sale or other taxable disposition of common stock as described in the next section.

The terms of pre-funded warrants provide for an adjustment to the exercise price or number of shares of our common stock for which the warrants may be exercised under certain circumstances. If such adjustment has the effect of merely preventing dilution, such adjustment may not be a taxable event. However, a holder of prefunded warrants may be treated as receiving a constructive distribution from us if the adjustment increases the holder's proportionate interest in our assets or earnings and profits (e.g., through an increase in the number of shares of our common stock that would be obtained upon exercise), including as a result of a distribution of cash or other property, such as other securities, to the holders of our common stock, or as a result of the issuance of a stock dividend to holders of our common stock, in each case that is taxable to such holders as a distribution. In addition, the failure to provide for an adjustment (or to adequately adjust) to prevent dilution may also result in a constructive distribution. Any constructive distribution received by a holder would be subject to tax in the same manner as if such holder received a cash distribution (as described above) from us equal to the fair market value of such increased proportionate interest. In the case of any constructive dividend, it is possible that this tax would be withheld from any amount payable or distributable to a non-U.S. holder by the applicable withholding agent, including cash distributions on other property or sale proceeds from warrants or other property subsequently paid or credited to such holder. For certain informational reporting purposes, we are required to determine the date and amount of any such constructive distributions and publicly report such information or report such information to the IRS and holders of our pre-funded warrants not exempt from information reporting. Proposed Treasury regulations, on which we may rely prior to the issuance of final regulations, specify how the date and amount of constructive distributions, and withholding obligations with respect thereto, are determined.

Gain on Disposition of Our Common Stock or Pre-Funded Warrants

Subject to the discussions below regarding backup withholding and foreign accounts, a Non-U.S. Holder generally will not be subject to U.S. federal income tax with respect to gain realized on a sale or other taxable disposition of our common stock or Pre-Funded Warrants unless: (a) the gain is effectively connected with the conduct of a trade or business of such holder in the United States (and, if required by an applicable income tax treaty, is attributable to a permanent establishment or fixed base that such holder maintains in the United States), (b) the Non-U.S. Holder is a nonresident alien individual and is present in the United States for 183 or more days in the taxable year of the disposition and certain other conditions are met or (c) we are or have been a “United States real property holding corporation” within the meaning of Code Section 897(c)(2) (a “USRPHC”) at any time within the shorter of the five-year period preceding such disposition or such holder’s holding period. In general, we would be a USRPHC if U.S. real property interests comprise (by fair market value) at least half of the value of our business assets and worldwide real

S-16

TABLE OF CONTENTS

property interests. We believe that we have not been and we are not, and do not anticipate becoming, a USRPHC, although there can be no assurance that we will not in the future become a USRPHC. Even if we are treated as a USRPHC, gain realized by a Non-U.S. Holder on a disposition of our common stock or Pre-Funded Warrants will not be subject to U.S. federal income tax so long as (1) the Non-U.S. Holder owned, directly, indirectly and constructively, no more than five percent of our common stock or Pre-Funded Warrants at all times within the shorter of (i) the five-year period preceding the disposition or (ii) the holder’s holding period and (2) our common stock is regularly traded on an established securities market. There can be no assurance that our common stock or Pre-Funded Warrants will continue to qualify as regularly traded on an established securities market. If any gain on your disposition is taxable because we are a USRPHC and a Non-U.S. Holder’s ownership of our common stock or Pre-Funded Warrants exceeds five percent, such holder will be taxed on such disposition generally in the manner applicable to United States persons, and in addition, a purchaser of such holder’s common stock may be required to withhold tax with respect to that obligation.

A Non-U.S. Holder described in (a) above will be required to pay tax on the net gain derived from the sale at regular U.S. federal income tax rates in the same manner as if such holder were a United States person, and corporate Non-U.S. Holders described in (a) above may be subject to the additional branch profits tax at a 30% rate or such lower rate as may be specified by an applicable income tax treaty. Gain described in (b) above will be subject to U.S. federal income tax at a flat 30% rate or such lower rate as may be specified by an applicable income tax treaty, which gain may be offset by certain U.S.-source capital losses (even though the Non-U.S. Holder is not considered a resident of the U.S.), provided that the Non-U.S. Holder has timely filed U.S. federal income tax returns with respect to such losses.

Non-U.S. Holders should consult their tax advisors regarding any applicable income tax treaties that may provide for different rules.

Information Reporting Requirements and Backup Withholding

Generally, we must report information to the IRS with respect to any distributions we pay on our common stock (even if the payments are exempt from withholding), including the amount of any such distributions, the name and address of the recipient, and the amount, if any, of tax withheld. A similar report is sent to the holder to whom any such distributions are paid. Pursuant to tax treaties or certain other agreements, the IRS may make its reports available to tax authorities in the recipient’s country of residence.

Backup withholding, currently at a 24% rate, generally will not apply to payments to a Non-U.S. Holder of dividends on or the gross proceeds of a disposition of our common stock provided the Non-U.S. Holder furnishes the required certification for its non-U.S. status, such as by providing a valid IRS Form W-8BEN, IRS Form W-8BEN-E or IRS Form W-8ECI, or otherwise establishes an exemption, and if the payor does not have actual knowledge, or reason to know, that the holder is a United States person who is not an exempt recipient.

Backup withholding is not an additional tax. If any amount is withheld under the backup withholding rules, the Non-U.S. Holder should consult with a U.S. tax advisor regarding the possibility of and procedure for obtaining a refund or a credit against the Non-U.S. Holder’s U.S. federal income tax liability, if any.

Foreign Accounts

Sections 1471 through 1474 of the Code (commonly referred to as “FATCA”) impose a U.S. federal withholding tax of 30% on certain payments to a “foreign financial institution” (as specifically defined under these rules) unless such institution enters into an agreement with the U.S. government to withhold on certain payments and to collect and provide to the U.S. tax authorities substantial information regarding U.S. account holders of such institution (which includes certain equity and debt holders of such institution, as well as certain account holders that are foreign entities with U.S. owners). FATCA also generally imposes a U.S. federal withholding tax of 30% on certain payments to a “non-financial foreign entity” (as specifically defined under these rules) unless such entity provides the withholding agent with either a certification that it does not have any substantial direct or indirect U.S. owners or provides information regarding substantial direct and indirect U.S. owners of the entity. An intergovernmental agreement between the United States and an applicable foreign country may modify those requirements. The withholding tax

S-17

TABLE OF CONTENTS

described above will not apply if the foreign financial institution or non-financial foreign entity otherwise qualifies for an exemption from the rules. Under certain circumstances, a Non-U.S. Holder might be eligible for refunds or credits of such taxes. FATCA currently applies to dividends paid on our common stock or Pre-Funded Warrants and would have applied also to payments of gross proceeds from the sale or other disposition of our common stock or Pre-Funded Warrants. However, the U.S. Treasury Department has released proposed regulations under FATCA providing for the elimination of the U.S. federal withholding tax of 30% applicable to gross proceeds of a sale or other disposition of property of a type that can produce U.S. source dividends or interest. Under these proposed Treasury Regulations (which may be relied upon by taxpayers prior to finalization), FATCA will not apply to gross proceeds from sales or other dispositions of our common stock or Pre-Funded Warrants.

Prospective investors are encouraged to consult with their own tax advisors regarding the possible implications of FATCA on their investment in our common stock or Pre-Funded Warrants.

EACH PROSPECTIVE INVESTOR SHOULD CONSULT ITS OWN TAX ADVISOR REGARDING THE TAX CONSEQUENCES OF PURCHASING, HOLDING AND DISPOSING OF OUR COMMON STOCK OR PRE-FUNDED WARRANTS, INCLUDING THE CONSEQUENCES OF ANY CHANGE IN APPLICABLE LAW AS WELL AS TAX CONSEQUENCES ARISING UNDER ANY STATE, LOCAL, NON-U.S. OR U.S. FEDERAL NON-INCOME TAX LAWS.

S-18

TABLE OF CONTENTS

DESCRIPTION OF SECURITIES

We are offering shares of our common stock and, in lieu of offering shares of our common stock to certain investors, pre-funded warrants to purchase up to shares of common stock.

The following is a brief summary of certain terms and conditions of the securities being offered in this offering.

Common Stock

As of the date of this prospectus supplement, our amended and restated certificate of incorporation authorizes us to issue 70,000,000 shares of common stock, par value $0.001 per share, and 5,000,000 shares of preferred stock, par value $0.001 per share. The material terms and provisions of our common stock and each other class of our securities which qualifies or limits our common stock are described under the caption “Description of Capital Stock” in the accompanying prospectus. Our common stock is listed on the Nasdaq Global Select Market under the symbol “SENS.”

Pre-Funded Warrants

The material terms and provisions of the pre-funded warrants being issued in this offering are summarized below. The following description is subject to, and qualified in its entirety by, the form of pre-funded warrant which will be filed as an exhibit to a Current Report on Form 8-K to be filed by us with the SEC in connection with this offering. You should review the form of pre-funded warrant for a complete description of the terms and conditions applicable to the pre-funded warrants. See “Where You Can Find More Information” on page S-28 of this prospectus supplement.

Exercisability. The pre-funded warrants will be immediately exercisable, at the option of each holder, in whole or in part, by delivering to us a duly executed exercise notice and by payment in full in immediately available funds for the number of shares of our common stock purchased upon such exercise. However, if a registration statement registering the issuance of the shares of our common stock underlying a pre-funded warrant held by holder under the Securities Act is not effective or available for the issuance of such shares to such holder at the time of exercise, the holder may only exercise the pre-funded warrant through a “cashless exercise,” in which case, the holder would receive upon such exercise, the net number of shares of our common stock determined according to the formula set forth in the pre-funded warrant. Apart from the limited circumstance where such a registration statement is not then effective or available, the exercise price must be paid by the holder in cash in immediately available funds.

Exercise Limitations. A holder (together with its affiliates and other attribution parties) may not exercise any portion of a pre-funded warrant to the extent that immediately prior to or after giving effect to such exercise the holder would own more than 9.99% (at the election of the holder prior to the issuance of the warrant) of our outstanding common stock immediately after exercise, which percentage may be changed at the holder’s election to a higher or lower percentage not in excess of 19.99% (if exceeding such percentage would result in a change of control under Nasdaq Listing Rule 5635(b) or any successor rule) upon 61 days’ notice to us subject to the terms of the pre-funded warrants.

Exercise Price. Each pre-funded warrant offered hereby has an initial exercise price per share equal to $0.001. The pre-funded warrants are immediately exercisable and may be exercised at any time until the pre-funded warrants are exercised in full. The exercise price and number of shares of our common stock issuable upon exercise is subject to adjustment in the event of stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting our common stock.

Transferability. Subject to compliance with any applicable securities laws, the pre-funded warrants are separately tradeable immediately after issuance at the option of the holders and may be transferred at the option of the holders.

No Listing. There is no established public trading market for the pre-funded warrants and we do not expect a market to develop. In addition, we do not intend to apply for listing of the pre-funded warrants on any securities exchange or recognized trading system, including Nasdaq. Without an active market, the liquidity of the pre-funded warrants will be limited.

S-19

TABLE OF CONTENTS

Fundamental Transactions. In the event of a fundamental transaction, as described in the pre-funded warrants and generally including any reorganization, recapitalization or reclassification of our common stock, the sale, transfer or other disposition of all or substantially all of our properties or assets, our consolidation or merger with or into another person, the acquisition of more than 50% of our outstanding common stock, or any person or group becoming the beneficial owner of more than 50% of the voting power represented by our outstanding common stock, the pre-funded warrants shall automatically be deemed to be exercised in full in a cashless exercise effective immediately prior to the consummation of such fundamental transaction, without regard to any limitations on exercise contained in the pre-funded warrants.

Rights as a Stockholder. Except for the right to participate in certain dividends and distributions and as otherwise provided in the pre-funded warrant or by virtue of a holder’s ownership of shares of our common stock, the holders of the pre-funded warrants do not have the rights or privileges of holders of our common stock, including any voting rights, until they exercise their pre-funded warrants.

Warrant Agent. We are acting as warrant agent for the pre-funded warrants.

S-20

TABLE OF CONTENTS

UNDERWRITING

We and the underwriters for the offering named below have entered into an underwriting agreement with respect to the common stock and Pre-Funded Warrants being offered. Subject to the terms and conditions of the underwriting agreement, each underwriter has severally agreed to purchase from us the number of shares of our common stock and Pre-Funded Warrants set forth opposite its name below. TD Securities (USA) LLC and Barclays Capital Inc. are the representatives of the underwriters.

Underwriter	Number of Shares	Number of Pre-Funded Warrants
TD Securities (USA) LLC
Barclays Capital Inc.
Mizuho Securities USA LLC
Lake Street Capital Markets, LLC
Total

The underwriting agreement provides that the obligations of the underwriters are subject to certain conditions precedent and that the underwriters have agreed, severally and not jointly, to purchase all of the shares and Pre-Funded Warrants sold under the underwriting agreement if any of these securities are purchased, other than those shares covered by the option to purchase additional shares described below. If an underwriter defaults, the underwriting agreement provides that the purchase commitments of the non-defaulting underwriters may be increased or the underwriting agreement may be terminated.

We have agreed to indemnify the underwriters against specified liabilities, including liabilities under the Securities Act, and to contribute to payments the underwriters may be required to make in respect thereof.

The underwriters are offering the shares and Pre-Funded Warrants, subject to prior sale, when, as and if issued to and accepted by them, subject to approval of legal matters by their counsel and other conditions specified in the underwriting agreement. The underwriters reserve the right to withdraw, cancel or modify offers to the public and to reject orders in whole or in part.

Option to Purchase Additional Shares. We have granted to the underwriters an option to purchase up to additional shares of common stock at the public offering price, less the underwriting discounts and commissions. This option is exercisable for a period of 30 days. To the extent that the underwriters exercise this option, the underwriters will purchase additional shares from us in approximately the same proportion as shown in the table above.

Discounts and Commissions. The following table shows the public offering price, underwriting discounts and commissions and proceeds, before expenses to us. These amounts are shown assuming both no exercise and full exercise of the underwriters’ option to purchase additional shares.

We estimate that the total expenses of the offering, excluding underwriting discounts and commissions, will be approximately $ and are payable by us. We have also agreed to reimburse the underwriters for certain of their expenses as set forth in the underwriting agreement, including legal fees incurred in the qualification of this offering with the Financial Regulatory Authority (“FINRA”), which amount is deemed to be underwriting compensation by FINRA.

Per Share

Per
Pre-Funded
Warrant

Total

Without Option

With Option

Public offering price

Underwriting discounts and commissions

Proceeds, before expenses, to Senseonics Holdings, Inc.

We are offering to those purchasers whose purchase of shares of common stock in this offering would result in the purchaser, together with its affiliates and certain related parties, beneficially owning more than 9.99% of our outstanding shares of common stock following the consummation of this offering, the

S-21

TABLE OF CONTENTS

opportunity to purchase, in lieu of shares of our common stock that would result in ownership in excess of 9.99%, Pre-Funded Warrants to purchase such excess shares of common stock. Each Pre-Funded Warrant will have an exercise price of $0.001.The purchase price for each such Pre-Funded Warrant equals the per share public offering price for the shares of common stock in this offering less the $0.001 per share exercise price of each such Pre-Funded Warrant.

The underwriters propose to offer the shares of common stock and Pre-Funded Warrants to the public at the public offering price set forth on the cover of this prospectus supplement. The underwriters may offer the shares of common stock and Pre-Funded Warrants to securities dealers at the public offering price less a concession not in excess of $ per share and $ per Pre-Funded Warrant. If all of the shares and Pre-Funded Warrants are not sold at the public offering price, the underwriters may change the offering price and other selling terms. Sales of any shares of common stock and Pre-Funded Warrants may be made by affiliates of the underwriters.

Our common stock is listed on the Nasdaq Global Select Market under the trading symbol “SENS.” We do not intend to list the Pre-Funded Warrants on the Nasdaq Global Select Market or any other national securities exchange or nationally recognized trading system.

Passive Market Making. In connection with the offering, underwriters and selling group members may engage in passive market making transactions in the common stock on The Nasdaq Global Select Market in accordance with Rule 103 of Regulation M under the Exchange Act during the period before the commencement of offers or sales of common stock and extending through the completion of distribution. A passive market maker must display its bids at a price not in excess of the highest independent bid of the security. However, if all independent bids are lowered below the passive market maker’s bid that bid must be lowered when specified purchase limits are exceeded.

Stabilization. In connection with this offering, the underwriters (and their affiliates) may engage in stabilizing transactions, overallotment transactions, syndicate covering transactions, penalty bids and purchases to cover positions created by short sales.

•

Stabilizing transactions permit bids to purchase shares of common stock so long as the stabilizing bids do not exceed a specified maximum, and are engaged in for the purpose of preventing or retarding a decline in the market price of the common stock while the offering is in progress.

•

Overallotment transactions involve sales by the underwriters of shares of common stock in excess of the number of shares the underwriters are obligated to purchase. This creates a syndicate short position which may be either a covered short position or a naked short position. In a covered short position, the number of shares over-allotted by the underwriters is not greater than the number of shares that they may purchase in the option to purchase additional shares. In a naked short position, the number of shares involved is greater than the number of shares in the option to purchase additional shares. The underwriters may close out any short position by exercising their option to purchase additional shares and/or purchasing shares in the open market.

•

Syndicate covering transactions involve purchases of common stock in the open market after the distribution has been completed in order to cover syndicate short positions. In determining the source of shares to close out the short position, the underwriters will consider, among other things, the price of shares available for purchase in the open market as compared with the price at which they may purchase shares through exercise of the option to purchase additional shares. If the underwriters sell more shares than could be covered by exercise of the option to purchase additional shares and, therefore, have a naked short position, the position can be closed out only by buying shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that after pricing there could be downward pressure on the price of the shares in the open market that could adversely affect investors who purchase in the offering.

•

Penalty bids permit the representatives to reclaim a selling concession from a syndicate member when the common stock originally sold by that syndicate member is purchased in stabilizing or syndicate covering transactions to cover syndicate short positions.

These stabilizing transactions, syndicate covering transactions and penalty bids may have the effect of raising or maintaining the market price of our common stock or preventing or retarding a decline in the

S-22

TABLE OF CONTENTS

market price of our common stock. As a result, the price of our common stock in the open market may be higher than it would otherwise be in the absence of these transactions. Neither we nor the underwriters make any representation or prediction as to the effect that the transactions described above may have on the price of our common stock. These transactions may be effected on the Nasdaq Global Select Market, in the over-the-counter market or otherwise and, if commenced, may be discontinued at any time.

Lock-Up Agreements. Pursuant to certain “lock-up” agreements, we and our executive officers, directors and certain of our other stockholders, have agreed, subject to certain exceptions, not to and will not cause or direct any of its affiliates to offer, sell, assign, transfer, pledge, contract to sell, or otherwise dispose of or announce the intention to otherwise dispose of, or enter into, or announce the intention to enter into any swap, hedge or similar agreement or arrangement (including, without limitation, the purchase or sale of, or entry into, any put or call option, or combination thereof, forward, swap or any other derivative transaction or instrument, however described or defined) that transfers, is designed to transfer or reasonably could be expected to transfer (whether by the stockholder or someone other than the stockholder) that transfers, in whole or in part, directly or indirectly the economic consequence of ownership of, directly or indirectly, or make any demand or request or exercise any right with respect to the registration of, or file with the SEC a registration statement under the Securities Act relating to, any common stock or securities convertible into or exchangeable or exercisable for any common stock without the prior written consent of TD Securities (USA) LLC and Barclays Capital Inc., for a period of 90 days after the date of the pricing of the offering.

This lock-up provision applies to common stock and to securities convertible into or exchangeable or exercisable for common stock. The exceptions permit us, among other things and subject to restrictions, to: (a) issue common stock, restricted stock units or options pursuant to employee benefit plans, (b) issue common stock upon conversion of outstanding securities or exercise of outstanding warrants, (c) issue shares of common stock pursuant to the Sales Agreement, dated August 6, 2025, by and between the Company and TD Securities (USA) LLC (“Sales Agreement”) after thirty (30) days following the date of the underwriting agreement, and (d) file registration statements on Form S-8. The exceptions permit parties to the “lock-up” agreements, among other things and subject to restrictions, to: (a) make certain gifts, (b) if the party is a corporation, partnership, limited liability company or other business entity, make transfers to any shareholders, partners, members of, or owners of similar equity interests in, the party, or to an affiliate of the party, if such transfer is not for value, and (c) if the party is a corporation, partnership, limited liability company or other business entity, make transfers in connection with the sale or transfer of all of the party’s capital stock, partnership interests, membership interests or other similar equity interests, as the case may be, or all or substantially all of the party’s assets, in any such case not undertaken for the purpose of avoiding the restrictions imposed by the “lock-up” agreement. In addition, the lock-up provision will not restrict broker-dealers from engaging in market making and similar activities conducted in the ordinary course of their business.

TD Securities (USA) LLC and Barclays Capital Inc., in their sole discretion, may release our common stock and other securities subject to the lock-up agreements described above in whole or in part at any time. When determining whether or not to release our common stock and other securities from lock-up agreements, TD Securities (USA) LLC and Barclays Capital Inc. will consider, among other factors, the holder’s reasons for requesting the release, the number of shares for which the release is being requested and market conditions at the time of the request.

Selling Restrictions

Canada. The common stock and Pre-Funded Warrants may be sold only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the common stock and Pre-Funded Warrants must be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus supplement (including any amendment thereto)

S-23

TABLE OF CONTENTS

contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser’s province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser’s province or territory for particulars of these rights or consult with a legal advisor.

Pursuant to section 3A.3 of National Instrument 33-105 Underwriting Conflicts (NI 33-105), the underwriters are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

Switzerland. The securities will not be offered, directly or indirectly, to the public in Switzerland and this prospectus does not constitute a public offering prospectus as that term is understood pursuant to article 652a or 1156 of the Swiss Federal Code of Obligations.

European Economic Area. In relation to each Member State of the European Economic Area (each, a “Member State”), no shares or Pre-Funded Warrants have been offered or will be offered pursuant to the offering to the public in that Member State prior to the publication of a prospectus in relation to the shares or Pre-Funded Warrants which has been approved by the competent authority in that Member State or, where appropriate, approved in another Member State and notified to the competent authority in that Member State, all in accordance with the Prospectus Regulation, except that shares may be offered to the public in that Member State at any time:

A. to any legal entity which is a qualified investor as defined under Article 2 the Prospectus Regulation;

B. to fewer than 150 natural or legal persons (other than qualified investors as defined under Article 2 the Prospectus Regulation), subject to obtaining the prior consent of the representatives for any such offer; or

C. in any other circumstances falling within Article 1(4) of the Prospectus Regulation,

provided that no such offer of the shares or Pre-Funded Warrants shall require us or any of the representatives to publish a prospectus pursuant to Article 3 of the Prospectus Regulation or supplement a prospectus pursuant to Article 23 of the Prospectus Regulation.

For the purposes of this provision, the expression an “offer to the public” in relation to shares and Pre-Funded Warrants in any Member State means the communication in any form and by any means of sufficient information on the terms of the offer and any shares or Pre-Funded Warrants to be offered so as to enable an investor to decide to purchase or subscribe for any shares or Pre-Funded Warrants, and the expression “Prospectus Regulation” means Regulation (EU) 2017/1129.

United Kingdom. No shares or Pre-Funded Warrants have been offered or will be offered pursuant to the offering to the public in the United Kingdom except that the shares and Pre-Funded Warrants may be offered to the public in the United Kingdom at any time:

where (i) the offer is conditional on the admission of the shares or Pre-Funded Warrants to trading on the London Stock Exchange plc’s main market (in reliance on the exception in paragraph 6(a) of Schedule 1 of the POATR) or (ii) the shares and Pre-Funded Warrants being offered are at the time of the offer already admitted to trading on London Stock Exchange plc’s main market (in reliance on the exception in paragraph 6(b) of Schedule 1 of the POATR);

to any qualified investor as defined in paragraph 15 of Schedule 1 of the POATR;

to fewer than 150 persons (other than qualified investors as defined in paragraph 15 of Schedule 1 of the POATR), subject to obtaining the prior consent of the global coordinator for any such offer; or

in any other circumstances falling within Part 1 of Schedule 1 of the POATR.

For the purposes of this provision, the expression an “offer to the public” in relation to the shares and Pre-Funded Warrants in the United Kingdom means the communication to any person which presents sufficient information on: (a) the shares and Pre-Funded Warrants to be offered; and (b) the terms on which

S-24

TABLE OF CONTENTS

they are to be offered, to enable an investor to decide to buy or subscribe for the shares and the expression “POATR” means the Public Offers and Admissions to Trading Regulations 2024.

Hong Kong. The shares and Pre-Funded Warrants have not been offered or sold and will not be offered or sold in Hong Kong, by means of any document, other than (a) to “professional investors” as defined in the Securities and Futures Ordinance (Cap. 571 of the Laws of Hong Kong) (the “SFO”) of Hong Kong and any rules made thereunder; or (b) in other circumstances which do not result in the document being a “prospectus” as defined in the Companies (Winding Up and Miscellaneous Provisions) Ordinance (Cap. 32 of Hong Kong) (the “CO”), or which do not constitute an offer to the public within the meaning of the CO. No advertisement, invitation or document relating to the shares or Pre-Funded Warrants has been or may be issued or has been or may be in the possession of any person for the purposes of issue, whether in Hong Kong or elsewhere, which is directed at, or the contents of which are likely to be accessed or read by, the public of Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to shares or Pre-Funded Warrants which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” as defined in the SFO and any rules made thereunder.

Singapore. Each underwriter has acknowledged that this prospectus has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, each underwriter has represented and agreed that it has not offered or sold any shares or Pre-Funded Warrants or caused the shares or Pre-Funded Warrants to be made the subject of an invitation for subscription or purchase and will not offer or sell any shares or Pre-Funded Warrants or cause the shares or Pre-Funded Warrants to be made the subject of an invitation for subscription or purchase, and has not circulated or distributed, nor will it circulate or distribute, this prospectus or any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the shares or Pre-Funded Warrants, whether directly or indirectly, to any person in Singapore other than:

A. to an institutional investor (as defined in Section 4A of the Securities and Futures Act (Chapter 289) of Singapore, as modified or amended from time to time (the “SFA”)) pursuant to Section 274 of the SFA;

B. to a relevant person (as defined in Section 275(2) of the SFA) pursuant to Section 275(1) of the SFA, or any person pursuant to Section 275(1A) of the SFA, and in accordance with the conditions specified in Section 275 of the SFA; or

C. otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA.

Where the shares or Pre-Funded Warrants are subscribed or purchased under Section 275 of the SFA by a relevant person which is:

a. a corporation (which is not an accredited investor (as defined in Section 4A of the SFA)) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or

b. a trust (where the trustee is not an accredited investor) whose sole purpose is to hold investments and each beneficiary of the trust is an individual who is an accredited investor,

securities or securities-based derivatives contracts (each term as defined in Section 2(1) of the SFA) of that corporation or the beneficiaries’ rights and interest (however described) in that trust shall not be transferred within six months after that corporation or that trust has acquired the shares pursuant to an offer made under Section 275 of the SFA except:

(i) to an institutional investor or to a relevant person, or to any person arising from an offer referred to in Section 275(1A) or Section 276(4)(i)(B) of the SFA;

(ii) where no consideration is or will be given for the transfer;

(iii) where the transfer is by operation of law;

(iv) as specified in Section 276(7) of the SFA; or

S-25

TABLE OF CONTENTS

(v) as specified in Regulation 37A of the Securities and Futures (Offers of Investments) (Securities and Securities-based Derivatives Contracts) Regulations 2018.

Singapore SFA Product Classification — In connection with Section 309B of the SFA and the CMP Regulations 2018, unless otherwise specified before an offer of shares, we have determined, and hereby notify all relevant persons (as defined in Section 309A(1) of the SFA), that the shares are “prescribed capital markets products” (as defined in the CMP Regulations 2018) and Excluded Investment Products (as defined in MAS Notice SFA 04-N12: Notice on the Sale of Investment Products and MAS Notice FAA-N16: Notice on Recommendations on Investment Products).

Israel. In the State of Israel this prospectus supplement shall not be regarded as an offer to the public to purchase shares of common stock or Pre-Funded Warrants under the Israeli Securities Law, 5728-1968, which requires a prospectus to be published and authorized by the Israel Securities Authority, if it complies with certain provisions of Section 15 of the Israeli Securities Law, 5728 – 1968, including, inter alia, if: (i) the offer is made, distributed or directed to not more than 35 investors, subject to certain conditions (the “Addressed Investors”); or (ii) the offer is made, distributed or directed to certain qualified investors defined in the First Addendum of the Israeli Securities Law, 5728 – 1968, subject to certain conditions (the “Qualified Investors”). The Qualified Investors shall not be taken into account in the count of the Addressed Investors and may be offered to purchase securities in addition to the 35 Addressed Investors. The company has not and will not take any action that would require it to publish a prospectus in accordance with and subject to the Israeli Securities Law, 5728 – 1968. We have not and will not distribute this prospectus or make, distribute or direct an offer to subscribe for our common stock or Pre-Funded Warrants to any person within the State of Israel, other than to Qualified Investors and up to 35 Addressed Investors.

Qualified Investors may have to submit written evidence that they meet the definitions set out in of the First Addendum to the Israeli Securities Law, 5728 – 1968. In particular, we may request, as a condition to be offered common stock or Pre-Funded Warrants, that Qualified Investors will each represent, warrant and certify to us and/or to anyone acting on our behalf: (i) that it is an investor falling within one of the categories listed in the First Addendum to the Israeli Securities Law, 5728 – 1968; (ii) which of the categories listed in the First Addendum to the Israeli Securities Law, 5728 – 1968 regarding Qualified Investors is applicable to it; (iii) that it will abide by all provisions set forth in the Israeli Securities Law, 5728 – 1968 and the regulations promulgated thereunder in connection with the offer to be issued common stock or Pre-Funded Warrants; (iv) that the shares of common stock that it will be issued are, subject to exemptions available under the Israeli Securities Law, 5728 – 1968: (a) for its own account; (b) for investment purposes only; and (c) not issued with a view to resale within the State of Israel, other than in accordance with the provisions of the Israeli Securities Law, 5728 – 1968; and (v) that it is willing to provide further evidence of its Qualified Investor status. Addressed Investors may have to submit written evidence in respect of their identity and may have to sign and submit a declaration containing, inter alia, the Addressed Investor’s name, address and passport number or Israeli identification number.

We have not authorized and do not authorize the making of any offer of securities through any financial intermediary on our behalf, other than offers made by the underwriters and their respective affiliates, with a view to the final placement of the securities as contemplated in this document. Accordingly, no purchaser of the shares or Pre-Funded Warrants, other than the underwriters, is authorized to make any further offer of shares or Pre-Funded Warrants on our behalf or on behalf of the underwriters.

Electronic Offer, Sale and Distribution of Shares. A prospectus in electronic format may be made available on the websites maintained by one or more of the underwriters or selling group members, if any, participating in this offering and one or more of the underwriters participating in this offering may distribute prospectuses electronically. The representatives may agree to allocate a number of shares or Pre-Funded Warrants to underwriters and selling group members for sale to their online brokerage account holders. Internet distributions will be allocated by the underwriters and selling group members that will make internet distributions on the same basis as other allocations. Other than the prospectus in electronic format, the information on these websites is not part of this prospectus or the registration statement of which this prospectus forms a part, has not been approved or endorsed by us or any underwriter in its capacity as underwriter, and should not be relied upon by investors.

S-26

TABLE OF CONTENTS

Other Relationships. Certain of the underwriters and their affiliates have provided, and may in the future provide, various investment banking, commercial banking and other financial services for us and our affiliates for which they have received, and may in the future receive, customary fees. The underwriters and certain of their affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities. In the ordinary course of their various business activities, the underwriters and certain of their affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers, and such investment and securities activities may involve securities and/or instruments of the issuer or its affiliates. The underwriters and certain of their affiliates may also communicate independent investment recommendations, market color or trading ideas and/or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments. TD Securities (USA) LLC is the sales agent under our sales agreement, pursuant to which we may offer and sell, from time to time, shares of our common stock by any method that is deemed to be an “at the market offering” under Rule 415(a)(4) under the Securities Act.

S-27

TABLE OF CONTENTS

LEGAL MATTERS

The validity of the securities being offered by this prospectus supplement will be passed upon for us by Cooley LLP. Certain legal matters will be passed upon for the underwriters in connection with this offering by Goodwin Procter LLP.

EXPERTS

The consolidated financial statements of Senseonics Holdings, Inc. and its subsidiaries as of December 31, 2025 and 2024, and for each of the years in the two-year period ended December 31, 2025 have been incorporated by reference herein in reliance upon the report of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

The audit report covering the December 31, 2025 consolidated financial statements contains an explanatory paragraph that states that the Company has determined that it may not meet its covenants as early as the third quarter of 2026. Further, the Company will require additional liquidity to continue its operations over the next twelve months. Therefore, the Company concluded that substantial doubt exists about its ability to continue as a going concern for the one-year period following the date the consolidated financial statements are issued. The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty.

WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s website at www.sec.gov. Copies of certain information filed by us with the SEC are also available on our website at www.senseonics.com/. Our website is not a part of this prospectus supplement and is not incorporated by reference in this prospectus supplement.

This prospectus supplement is part of a registration statement that we filed with the SEC. The registration statement contains more information than this prospectus supplement and the accompanying prospectus regarding us and the securities, including certain exhibits and schedules. You can obtain a copy of the registration statement from the SEC’s internet site.

S-28

TABLE OF CONTENTS

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to incorporate by reference in this prospectus supplement and the accompanying prospectus much of the information we file with the SEC, which means that we can disclose important information to you by referring you to those publicly available documents. The information that we incorporate by reference in this prospectus supplement and the accompanying prospectus is considered to be part of this prospectus supplement and the accompanying prospectus. Because we are incorporating by reference future filings with the SEC, this prospectus supplement and the accompanying prospectus is continually updated and those future filings may modify or supersede some of the information included or incorporated in this prospectus supplement and the accompanying prospectus. This means that you must look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus supplement, the accompanying prospectus or any document previously incorporated by reference have been modified or superseded. This prospectus supplement and the accompanying prospectus incorporate by reference the documents listed below and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (in each case, other than those documents or the portions of those documents not deemed to be filed) until the offering of the securities under the registration statement is terminated or completed:

•

our Annual Report on Form 10-K for the year ended December 31, 2025, filed with the SEC on March 2, 2026;

•

our Current Reports on Form 8-K filed with the SEC on January 2, 2026, January 12, 2026 (Item 8.01 only) and March 12, 2026 to the extent the information in such reports is filed and not furnished;

•

our Definitive Proxy Statement on Schedule 14A, filed with the SEC on April 6, 2026, as amended by the Amendment No. 1 to the Definitive Proxy Statement on Schedule 14A, filed with the SEC on April 9, 2026 (other than the portions that are not required to be incorporated by reference into our Annual Report on Form 10-K for the year ended December 31, 2025); and

•

the description of our common stock contained in Exhibit 4.3 to our Annual Report on Form 10-K for the year ended December 31, 2025, filed with the SEC on March 2, 2026, including any amendments or reports filed for the purposes of updating this description.

You may request a copy of these filings, at no cost, by writing or telephoning us at the following address or phone number:

Senseonics Holdings, Inc.
Attn: Investor Relations
20451 Seneca Meadows Parkway
Germantown, MD 20876-7005
Telephone: (301) 515-7260

S-29

TABLE OF CONTENTS

PROSPECTUS

$300,000,000
Common Stock
Preferred Stock
Debt Securities
Warrants

From time to time, we may offer and sell up to an aggregate amount of $300,000,000 of any combination of the securities described in this prospectus, either individually or in combination with other securities. We may also offer common stock or preferred stock upon conversion of debt securities, common stock upon conversion of preferred stock, or common stock, preferred stock or debt securities upon the exercise of warrants.

We will provide the specific terms of these offerings and securities in one or more supplements to this prospectus. We may also authorize one or more free writing prospectuses to be provided to you in connection with these offerings. The prospectus supplement and any related free writing prospectuses may also add, update or change information contained in this prospectus. You should carefully read this prospectus, the applicable prospectus supplement and any related free writing prospectuses, as well as any documents incorporated by reference, before buying any of the securities being offered.

Our common stock is listed on the NYSE American under the trading symbol “SENS.” On August 5, 2025, the last reported sale price of our common stock was $0.51 per share. The applicable prospectus supplement will contain information, where applicable, as to other listings, if any, on the NYSE American or other securities exchange of the securities covered by the applicable prospectus supplement.

We are a “smaller reporting company” under the federal securities laws and are subject to reduced public company reporting requirements. See the section entitled “Prospectus Summary — Implications of Being a Smaller Reporting Company.”

This prospectus may not be used to consummate a sale of securities unless accompanied by a prospectus supplement.

The securities may be sold by us directly to investors, through agents designated from time to time or to or through underwriters or dealers, on a continuous or delayed basis. The supplements to this prospectus will provide the specific terms of the plan of distribution. If any agents, underwriters or dealers are involved in the sale of any securities with respect to which this prospectus is being delivered, the names of such agents, underwriters or dealers and any applicable fees, commissions, discounts and options to purchase additional securities will be set forth in a prospectus supplement. The price to the public of such securities and the net proceeds we expect to receive from such sale will also be set forth in a prospectus supplement.

Investing in our securities involves a high degree of risk. Before making an investment decision, you should review carefully and consider all of the information set forth in this prospectus and the documents incorporated by reference in this prospectus. See the section entitled “Risk Factors” beginning on page 7 of this prospectus and in the documents incorporated by reference into this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is August 18, 2025.

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we have filed with the Securities and Exchange Commission, or SEC, using a “shelf” registration process. Under this shelf registration statement, we may, from time to time, offer and sell, either individually or in combination, in one or more offerings, with an aggregate offering price of up to $300,000,000 of any combination of the securities described in this prospectus.

This prospectus provides you with a general description of the securities we may offer. Each time we offer securities under this prospectus, we will provide a prospectus supplement that will contain more specific information about the terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. The prospectus supplement and any related free writing prospectuses that we may authorize to be provided to you may also add, update or change any of the information contained in this prospectus or in the documents that we have incorporated by reference into this prospectus. We urge you to read carefully this prospectus, any applicable prospectus supplement and any free writing prospectuses we have authorized for use in connection with a specific offering, together with the information incorporated herein by reference as described under the heading “Incorporation of Certain Information by Reference,” before buying any of the securities being offered.

This prospectus may not be used to consummate a sale of securities unless it is accompanied by a prospectus supplement.

We have not authorized any other person to provide you with any information or to make any representations other than those contained in, or incorporated by reference into, this prospectus, any related prospectus supplement and any free writing prospectuses prepared by or on behalf of us or to which we have referred you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. You should assume that the information appearing in this prospectus, any related prospectus supplement and the documents incorporated by reference into this prospectus, any related prospectus supplement and in any free writing prospectuses that we may authorize for use in connection with this offering, is accurate only as of the date of those respective documents. Our business, financial condition, results of operations and prospects may have changed since those dates. You should read this prospectus, any related prospectus supplement, the documents incorporated by reference into this prospectus, and any free writing prospectuses that we may authorize for use in connection with this offering, in their entirety before making an investment decision. You should also read and consider the information in the documents to which we have referred you in the sections of this prospectus captioned “Where You Can Find Additional Information” and “Incorporation of Certain Information by Reference.”

We are not making an offer to sell or soliciting an offer to buy our securities in any jurisdiction in which an offer or solicitation is not authorized or in which the person making that offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation. We are offering to sell, and seeking offers to buy, our securities only in jurisdictions where offers and sales are permitted. The distribution of this prospectus and any related prospectus supplement or free writing prospectuses and the offering of our securities in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus and any related prospectus supplement or free writing prospectuses must inform themselves about, and observe any restrictions relating to, the offering of our securities and the distribution of this prospectus and any related prospectus supplement outside the United States. This prospectus and any related prospectus supplement or free writing prospectuses does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus and any related prospectus supplement by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

We obtained the industry and market data in this prospectus, including the information incorporated by reference herein, from our own research as well as from industry and general publications, surveys and studies conducted by third parties. These data involve a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. In addition, projections, assumptions and estimates of our future performance and the future performance of the industry in which we operate is necessarily subject to a high degree of uncertainty and risk due to a variety of factors, including those described in “Risk

TABLE OF CONTENTS

Factors” and elsewhere in this prospectus, any related prospectus supplement, documents incorporated by reference into this prospectus and any related or free writing prospectuses. These and other factors could cause results to differ materially from those expressed in the estimates made by the independent parties and by us.

This prospectus and any related prospectus supplement, including the information incorporated by reference into this prospectus and any related prospectus supplement, include trademarks, service marks and trade names owned by us or others. All trademarks, service marks and trade names included or incorporated by reference in this prospectus, any related prospectus supplement or any related free writing prospectuses are the property of their respective owners.

Unless otherwise indicated or the context otherwise requires, all references in this prospectus to the “Company,” “we,” “our,” “ours,” “us” or similar terms refer to Senseonics Holdings, Inc. and its consolidated subsidiaries and affiliated entities, as appropriate, including its consolidated VIEs (as defined below).

TABLE OF CONTENTS

PROSPECTUS SUMMARY

The Company

We are a medical technology company focused on the development and manufacturing of glucose monitoring products designed to transform lives in the global diabetes community with differentiated, long-term implantable glucose management technology. Our implantable continuous glucose monitoring, or CGM, systems, including the Eversense E3 system, or Eversense E3, and the Eversense 365 system, or Eversense 365, and, together with Eversense E3, Eversense or the Eversense Systems, are designed to continually and accurately measure glucose levels in people with diabetes via an under-the-skin sensor, a removable and rechargeable smart transmitter, and a convenient app for real-time diabetes monitoring and management for a period of up to six months in the case of Eversense E3 and up to twelve months in the case of Eversense 365, as compared to seven to 15 days for non-implantable CGM systems. In February 2022, Eversense E3, a 180 day CGM system, was approved by the FDA and Ascensia Diabetes Care Holdings AG, or Ascensia, began commercializing Eversense E3 in the United States in the second quarter of 2022. In June 2022, we affixed the CE mark to the extended life Eversense E3 system and Ascensia began commercialization in select markets in Europe during the third quarter of 2022. In September 2024, Eversense 365, a 365-day extended life CGM system, was approved by the FDA and Ascensia began commercializing Eversense 365 in the United States in the fourth quarter of 2024.

Our net revenues are derived from sales of the Eversense Systems, which includes the Eversense sensor pack containing the sensor, insertion tool, and adhesive patches, the Eversense smart transmitter pack containing the transmitter and charger and in some cases the procedure revenue associated with insertions and removals.

We are in the early commercialization stages of the Eversense brand and are focused on driving awareness of our CGM system amongst people with diabetes and their healthcare providers. In both the United States and our overseas markets, we have entered into strategic partnerships and distribution agreements that allow third party collaborators with direct sales forces and established distribution systems to market and promote Senseonics various Eversense CGM systems and future generation products, including our “Gemini” product variation to allow for a 2-in-1 glucose monitoring system combining the functionality of CGM and flash glucose monitoring, in an implantable sensor with battery that may be utilized with a smart transmitter to get continuous glucose readings and alerts, or be utilized through a swipe over the sensor with a smart phone to get on-demand glucose reading without a smart transmitter and our “Freedom” product variation which would include Bluetooth in the sensor eliminating the on-body component.

Risks Associated with Our Business

Our business is subject to a number of risks of which you should be aware before making an investment decision. These risks are discussed more fully in the “Risk Factors” section of this prospectus immediately following this prospectus summary and in the “Risk Factors” sections in our Annual Report on Form 10-K for the year ended December 31, 2024 and Quarterly Report on Form 10-Q for the quarter ended June 30, 2025, which are incorporated by reference in this prospectus.

Company Information

We were originally incorporated as ASN Technologies, Inc. in Nevada on June 26, 2014. In 2015, we acquired Senseonics, Incorporated, a medical technology company focused on the design, development and commercialization of glucose monitoring systems to improve the lives of people with diabetes by enhancing their ability to manage their disease with relative ease and accuracy. From its inception in 1996 until 2010, Senseonics, Incorporated devoted substantially all of its resources to researching various sensor technologies and platforms. Beginning in 2010, the company narrowed its focus to designing, developing and refining a commercially viable glucose monitoring system.

TABLE OF CONTENTS

subsidiaries of Senseonics, Incorporated formed in April 2024 and July 2024, respectively. In November 2024, Eon Management Services, LLC entered into the Administrative Agreement with several professional corporations, or Eon Care PCs, which are consolidated as variable interest entities, or VIEs. The wholly owned entities and Eon Care PCs, or collectively, Eon Care, were established to support patient access to the Eversense system by providing convenient Eversense insertion and training services.

Available Information

Implications of Being a Smaller Reporting Company

The Securities We May Offer

We may offer shares of our common stock and preferred stock, various series of debt securities and/or warrants to purchase any of such securities, either individually or in combination, with an aggregate offering price of up to $300,000,000 from time to time under this prospectus, together with the applicable prospectus supplement and any related free writing prospectuses, at prices and on terms to be determined by market conditions at the time of any offering. We may also offer common stock, preferred stock and/or debt securities upon the exercise of warrants. This prospectus provides you with a general description of the securities we may offer. Each time we offer a type or series of securities under this prospectus, we will provide a prospectus supplement that will describe the specific amounts, prices and other important terms of the securities, including, to the extent applicable:

•

designation or classification;

•

aggregate principal amount or aggregate offering price;

•

maturity date, if applicable;

•

original issue discount, if any;

•

rates and times of payment of interest or dividends, if any;

•

redemption, conversion, exercise, exchange or sinking fund terms, if any;

•

conversion or exchange prices or rates, if any, and, if applicable, any provisions for changes to or adjustments in the conversion or exchange prices or rates and in the securities or other property receivable upon conversion or exchange;

•

ranking, if applicable;

•

restrictive covenants, if any;

•

voting or other rights, if any; and

•

material or special U.S. federal income tax considerations, if any.

The applicable prospectus supplement and any related free writing prospectuses that we may authorize to be provided to you may also add, update or change any of the information contained in this prospectus

TABLE OF CONTENTS

or in the documents we have incorporated by reference. However, no prospectus supplement or free writing prospectuses will offer a security that is not registered and described in this prospectus at the time of the effectiveness of the registration statement of which this prospectus is a part.

THIS PROSPECTUS MAY NOT BE USED TO CONSUMMATE A SALE OF SECURITIES UNLESS IT IS ACCOMPANIED BY A PROSPECTUS SUPPLEMENT.

We may sell the securities directly to investors or to or through agents, underwriters or dealers. We and our agents, underwriters or dealers, reserve the right to accept or reject all or part of any proposed purchase of securities. If we do offer securities to or through agents, underwriters or dealers, we will include in the applicable prospectus supplement:

•

the names of those agents, underwriters or dealers;

•

applicable fees, discounts and commissions to be paid to them;

•

details regarding over-allotment options, if any; and

•

the estimated net proceeds to us.

Common Stock. We may issue shares of our common stock from time to time. The holders of our common stock are entitled to one vote for each share held of record on all matters submitted to a vote of stockholders. Subject to preferences that may be applicable to any outstanding shares of preferred stock, the holders of common stock are entitled to receive ratably such dividends as may be declared by our board of directors out of legally available funds. Upon our liquidation, dissolution or winding up, holders of our common stock are entitled to share ratably in all assets remaining after payment of liabilities and the liquidation preferences of any outstanding shares of preferred stock. Holders of common stock have no preemptive or subscription rights and no right to convert their common stock into any other securities. There are no redemption or sinking fund provisions applicable to our common stock. In this prospectus, we have summarized certain general features of the common stock under the section entitled “Description of Capital Stock — Common Stock.” We urge you, however, to read the applicable prospectus supplement (and any related free writing prospectuses that we may authorize to be provided to you) related to any common stock being offered.

Preferred Stock. We may issue shares of our preferred stock from time to time, in one or more series. Our board of directors will determine the designations, voting powers, preferences and rights of the preferred stock, as well as the qualifications, limitations or restrictions thereof, including dividend rights, conversion rights, preemptive rights, terms of redemption or repurchase, liquidation preferences, sinking fund terms and the number of shares constituting any series or the designation of any series. Convertible preferred stock will be convertible into our common stock or exchangeable for other securities. Conversion may be mandatory or at your option and would be at prescribed conversion rates.

If we sell any series of preferred stock under this prospectus as supplemented by a prospectus supplement, and if applicable, free writing prospectus, we will fix the designations, voting powers, preferences and rights of the preferred stock of each series we issue under this prospectus, as well as the qualifications, limitations or restrictions thereof, in the certificate of designation relating to that series. We will file as an exhibit to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of any certificate of designation that contains the terms of the series of preferred stock we are offering. In this prospectus, we have summarized certain general features of the preferred stock under the section entitled “Description of Capital Stock — Preferred Stock.” We urge you, however, to read the applicable prospectus supplement (and any related free writing prospectuses that we may authorize to be provided to you) related to the series of preferred stock being offered, as well as the complete certificate of designation that contains the terms of the applicable series of preferred stock.

Debt Securities. We may issue debt securities from time to time, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. The senior debt securities will rank equally with any other unsecured and unsubordinated debt. The subordinated debt securities will be subordinate and junior in right of payment, to the extent and in the manner described in the instrument governing the debt, to all of our senior indebtedness. Convertible debt securities will be convertible into or

TABLE OF CONTENTS

exchangeable for our common stock or other securities. Conversion may be mandatory or at the holder’s option and would be at prescribed conversion rates.

Any debt securities issued under this prospectus will be issued under one or more documents called indentures, which are contracts between us and a national banking association or other eligible party, as trustee. In this prospectus, we have summarized certain general features of the debt securities under “Description of Debt Securities.” We urge you, however, to read the applicable prospectus supplement (and any free writing prospectuses that we may authorize to be provided to you) related to the series of debt securities being offered, as well as the complete indentures that contain the terms of the debt securities. We have filed the form of indenture as an exhibit to the registration statement of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of the debt securities being offered will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from reports that we file with the SEC.

Warrants. We may issue warrants for the purchase of common stock, preferred stock and/or debt securities in one or more series. We may issue warrants independently or in combination with common stock, preferred stock and/or debt securities, and the warrant may be attached to or separate from these securities. In this prospectus, we have summarized certain general features of the warrants under “Description of Warrants.” We urge you, however, to read the applicable prospectus supplement (and any related free writing prospectuses that we may authorize to be provided to you) related to the particular series of warrants being offered, as well as any warrant agreements and warrant certificates that contain the terms of the warrants. We have filed forms of the warrant agreements and forms of warrant certificates containing the terms of the warrants that may be offered as exhibits to the registration statement of which this prospectus is a part. We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of warrant and/or the warrant agreement and warrant certificate, as applicable, that contain the terms of the particular series of warrants we are offering, and any supplemental agreements, before the issuance of such warrants.

Any warrants issued under this prospectus may be evidenced by warrant certificates. Warrants also may be issued under an applicable warrant agreement that we enter into with a warrant agent. We will indicate the name and address of the warrant agent, if applicable, in the prospectus supplement relating to the particular series of warrants being offered.

Use of Proceeds

Except as described in any applicable prospectus supplement or in any free writing prospectuses we have authorized for use in connection with a specific offering, we currently intend to use the net proceeds from the sale of the securities offered by us hereunder, if any, for general corporate purposes, including but not limited to, research and development expenses, general and administrative expenses, sales and marketing expenses, and capital expenditures, or for any other purpose we describe in the applicable prospectus supplement. We may also use a portion of the net proceeds to in-license, invest in or acquire businesses, assets or technologies that we believe are complementary to our own, although we have no current plans, commitments or agreements with respect to any acquisitions. See the section entitled “Use of Proceeds” in this prospectus.

Listing on the NYSE American

Our common stock is listed on the NYSE American under the symbol “SENS.” The applicable prospectus supplement will contain information, where applicable, as to other listings, if any, on the NYSE American or other securities exchange of the securities covered by the applicable prospectus supplement.

TABLE OF CONTENTS

RISK FACTORS

Investing in our securities involves a high degree of risk. Before deciding whether to invest in our securities, you should consider carefully the risks and uncertainties described under the section entitled “Risk Factors” contained in the applicable prospectus supplement and any related free writing prospectuses, and discussed under the section entitled “Risk Factors” contained in our most recent Annual Report on Form 10-K and in our subsequent Quarterly Reports on Form 10-Q, as well as any amendments thereto reflected in subsequent filings with the SEC, which are incorporated by reference into this prospectus in their entirety, together with other information in this prospectus, the documents incorporated by reference and any applicable prospectus supplement and free writing prospectuses that we may authorize for use in connection with this offering. The risks described in these documents are not the only ones we face, but those that we consider to be material. There may be other unknown or unpredictable economic, business, competitive, regulatory or other factors that could have material adverse effects on our future results. Past financial performance may not be a reliable indicator of future performance, and historical trends should not be used to anticipate results or trends in future periods. If any of these risks actually occurs, our business, financial condition, results of operations or cash flow could be seriously harmed. This could cause the trading price of our common stock to decline, resulting in a loss of all or part of your investment. Please also read carefully the section below entitled “Special Note Regarding Forward-Looking Statements.”

TABLE OF CONTENTS

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and any accompanying prospectus supplement and the documents we have filed with the SEC that are incorporated by reference herein and therein contain forward-looking statements about us and our industry that involve substantial risks and uncertainties. All statements other than statements of historical fact contained in this prospectus, the applicable prospectus supplement, and the documents we have filed with the SEC that are incorporated by reference herein and therein, including statements regarding our plans, objectives, goals, strategies, future events, future revenues or performance, financing needs, plans, or intentions relating to product candidates and markets and business trends, are forward-looking statements. Discussions containing these forward-looking statements may be found, among other places, in the section entitled “Risk Factors” in this prospectus and any applicable prospectus supplement, as well as under the sections entitled “Business,” “Risk Factors,” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” contained in the documents incorporated by reference herein and therein. We have based these forward-looking statements largely on our current expectations and projections. In some cases, you can identify forward-looking statements because they contain words such as “anticipate,” “believe,” “can,” “contemplate,” “continue,” “could,” “design,” “estimate,” “expect,” “intend,” “may,” “might,” “objective,” “plan,” “potential,” “predict,” “project,” “shall,” “should,” “target,” “will,” or “would,” or the negative of these words or other similar terms or expressions. These statements involve known and unknown risks, uncertainties, and other factors which may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. Forward-looking statements include, but are not limited to, statements about:

•

the success of our collaboration and commercialization agreement with Ascensia;

•

the timing of product launches;

•

the clinical utility of Eversense;

•

our ability to develop future generations of Eversense;

•

our ability to service our outstanding indebtedness;

•

the timing and availability of data from our clinical trials;

•

the timing of our planned regulatory filings and potential regulatory approvals and CE Certificates of Conformity;

•

our future development priorities;

•

our ability to obtain adequate reimbursement and third-party payor coverage for Eversense;

•

the purchasing patterns of our customers, including as a result of seasonality, which may be impacted by the timing and use of deductibles and out-of-pocket expense limits;

•

our expectations about the willingness of healthcare providers to recommend Eversense to people with diabetes;

•

our commercialization, marketing and manufacturing capabilities and strategy;

•

our ability to comply with applicable regulatory requirements;

•

our ability to maintain our intellectual property position;

•

our estimates regarding the size of, and future growth in, the market for continuous glucose monitoring systems;

•

the impact of certain rights that we previously granted to Abbott Laboratories in connection with a private placement offering;

•

the accuracy of our estimates regarding future expenses, future revenue, capital requirements, and need for additional financing;

•

the period over which we estimate our existing cash and cash equivalents will be sufficient to fund our future operating expenses and capital expenditure requirements;

TABLE OF CONTENTS

•

our use of cash and other resources, including our expected use of proceeds from any offering under this prospectus; and

•

other risks and uncertainties, including those listed under the caption “Risk Factors.”

These forward-looking statements reflect our management’s beliefs and views with respect to future events and are based on estimates and assumptions as of the date the statement is made and are subject to risks and uncertainties. In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date the statement is made, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and investors are cautioned not to unduly rely upon these statements. We discuss many of the risks associated with the forward-looking statements in greater detail under the heading “Risk Factors” included in this prospectus, the applicable prospectus supplement, in any free writing prospectuses we may authorize for use in connection with a specific offering, and in our most recent Annual Report on Form 10-K and in our subsequent Quarterly Reports on Form 10-Q, as well as any amendments thereto reflected in subsequent filings with the SEC, which are incorporated by reference into this prospectus in their entirety. You should evaluate all forward-looking statements in the context of these risks and uncertainties. Moreover, we operate in a very competitive and rapidly changing environment. New risks emerge from time to time. It is not possible for our management to predict all risks, nor can we assess the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements we may make. Given these uncertainties, you should not place undue reliance on these forward-looking statements.

You should carefully read this prospectus, any applicable prospectus supplement, together with the documents we have filed with the SEC that are incorporated by reference, and any free writing prospectuses that we may authorize for use in connection with a specific offering completely and with the understanding that our actual future results may be materially different from what we expect. We qualify all of the forward-looking statements in the foregoing documents by these cautionary statements.

Except as required by law, we assume no obligation to update these forward-looking statements publicly, or to update the reasons actual results could differ materially from those anticipated in any forward-looking statements, whether as a result of new information, future events, or otherwise.

TABLE OF CONTENTS

USE OF PROCEEDS

Except as described in any prospectus supplement or in any related free writing prospectus that we may authorize to be provided to you in connection with a specific offering, we currently intend to use the net proceeds from the sale of securities under this prospectus for general corporate purposes, including but not limited to, research and development expenses, general and administrative expenses, sales and marketing expenses, and capital expenditures. We may also use a portion of the net proceeds to in-license, invest in or acquire businesses, assets or technologies that we believe are complementary to our own, although we have no current plans, commitments or agreements with respect to any acquisitions. As of the date of this prospectus, we cannot specify with certainty all of the particular uses of the net proceeds, if any, from the sale of securities under this prospectus. Accordingly, we will retain broad discretion over the use of such proceeds. We will set forth in the applicable prospectus supplement or free writing prospectus our intended use of the net proceeds received from the sale of any securities sold pursuant to the prospectus supplement or free writing prospectus. Pending the use of the net proceeds as described above, we intend to invest the net proceeds in investment-grade, interest-bearing instruments.

TABLE OF CONTENTS

DESCRIPTION OF CAPITAL STOCK

The following description of our capital stock and certain provisions of our amended and restated certificate of incorporation, as amended, or the restated certificate, our amended and restated bylaws, as amended, or the restated bylaws, and applicable provisions of the General Corporation Law of the State of Delaware, or the DGCL, are summaries and are qualified by reference to the restated certificate and the restated bylaws, which are included as exhibits to the registration statement of which this prospectus is part, and the DGCL.

General

The restated certificate authorizes the issuance of up to 1,400,000,000 shares of common stock, $0.001 par value per share, and 5,000,000 shares of preferred stock, $0.001 par value per share, 30,000 of which shares of preferred stock were designated as Series A Convertible Preferred Stock, 12,000 of which shares of preferred stock were designated as Series B Convertible Preferred Stock, and the remaining 4,958,000 of which shares of preferred stock were undesignated as of August 4, 2025. The Company’s board of directors may establish the rights and preferences of the preferred stock from time to time. As of August 4, 2025, we had outstanding 814,680,910 shares of common stock, no shares of Series B Convertible Preferred Stock and no shares of Series A Convertible Preferred Stock.

Common Stock

Voting

Each holder of our common stock is entitled to one vote for each share on all matters submitted to a vote of the stockholders, including the election of directors. Under our restated certificate and restated bylaws, our stockholders do not have cumulative voting rights. Because of this, the holders of a majority of the shares of common stock entitled to vote in any election of directors can elect all of the directors standing for election, if they should so choose.

Dividends

Holders of common stock are entitled to receive ratably those dividends, if any, as may be declared from time to time by the board of directors out of legally available funds.

Liquidation

In the event of the Company’s liquidation, dissolution or winding up, holders of common stock will be entitled to share ratably in the net assets legally available for distribution to stockholders.

Rights, Preferences, and Privileges

Holders of common stock have no preemptive, conversion or subscription rights and there are no redemption or sinking fund provisions applicable to the common stock. The rights, preferences and privileges of the holders of common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of preferred stock that the Company may designate in the future.

Fully Paid and Nonassessable

All of our outstanding shares of common stock are fully paid and nonassessable.

Preferred Stock

Pursuant to our restated certificate, our board of directors has the authority, without further action by the stockholders (unless such stockholder action is required by applicable law or stock exchange listing rules), to designate and issue up to 5,000,000 shares of preferred stock in one or more series, to establish from time to time the number of shares to be included in each such series, to fix the designations, powers, preferences, privileges and relative participating, optional or special rights and the qualifications, limitations

TABLE OF CONTENTS

or restrictions thereof, including dividend rights, conversion rights, voting rights, terms of redemption and liquidation preferences, any or all of which may be greater than the rights of the common stock, and to increase or decrease the number of shares of any such series, but not below the number of shares of such series then outstanding.

Our board of directors, without stockholder approval, can issue preferred stock with voting, conversion or other rights that could adversely affect the voting power and other rights of the holders of common stock. Preferred stock could be issued quickly with terms designed to delay or prevent a change in control of our company or make removal of management more difficult. Additionally, the issuance of preferred stock may have the effect of decreasing the market price of the common stock and may adversely affect the voting power of holders of common stock and reduce the likelihood that common stockholders will receive dividend payments and payments upon liquidation.

Warrants

As of August 5th, 2025, we had outstanding warrants to purchase an aggregate of 83,951,061, 116,581, 63,025, 80,645, 45,714,286, 832,362 and 347,887 shares of common stock at an exercise price of $0.001, $3.86, $2.38, $1.86, $0.35, $0.6007 and $0.5749 per share, respectively. These warrants do not expire, expire on June 30, 2026, November 22, 2026, March 29, 2027, April 24, 2030, September 8, 2030 and January 2, 2031, respectively. The number of shares of common stock issuable upon the exercise of each warrant is subject to adjustment from time to time upon the occurrence of specified events.

Anti-Takeover Effects of Provisions of Our Restated Certificate, Our Restated Bylaws, and Delaware Law

Section 203 of the Delaware General Corporation Law

We are subject to Section 203 of the DGCL. Section 203 generally prohibits a public Delaware corporation from engaging in a “business combination” with an “interested stockholder” for a period of three years following the time that such stockholder became an interested stockholder, unless:

•

prior to such time the board of directors of the corporation approved either the business combination or the transaction which resulted in the stockholder becoming an interested stockholder;

•

upon consummation of the transaction which resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, excluding for purposes of determining the voting stock outstanding (but not the outstanding voting stock owned by the interested stockholder) those shares owned (1) by persons who are directors and also officers and (2) employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or

•

at or subsequent to such time, the business combination is approved by the board of directors and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of at least 662∕3% of the outstanding voting stock which is not owned by the interested stockholder.

Section 203 defines a business combination to include:

•

any merger or consolidation involving the corporation or any direct or indirect majority-owned subsidiary of the corporation and the interested stockholder;

•

any sale, transfer, pledge or other disposition of 10% or more of the assets of the corporation involving the interested stockholder (in one transaction or a series of transactions);

•

subject to certain exceptions, any transaction that results in the issuance or transfer by the corporation or by any direct or indirect majority-owned subsidiary of the corporation of any stock of the corporation or of such subsidiary to the interested stockholder;

•

any transaction involving the corporation or any direct or indirect majority-owned subsidiary of the corporation that has the effect, directly or indirectly, of increasing the proportionate share of the stock or any class or series of the corporation beneficially owned by the interested stockholder; or

TABLE OF CONTENTS

•

any receipt by the interested stockholder of the benefit, directly or indirectly, of any loans, advances, guarantees, pledges, or other financial benefits by or through the corporation.

In general, Section 203 defines an “interested stockholder” as any entity or person who, together with the person’s affiliates and associates, beneficially owns, or within three years prior to the time of determination of interested stockholder status did own, 15% or more of the outstanding voting stock of the corporation.

Choice of Forum

Our restated certificate provides that the Court of Chancery of the State of Delaware will be the exclusive forum for (i) any derivative action or proceeding brought on our behalf; (ii) any action asserting a claim against any director, officer or other employee of ours for breach of a fiduciary duty owed to us or our stockholders; (iii) any action asserting a claim against us arising pursuant to any provision of the DGCL, our restated certificate or restated bylaws; or (iv) any action asserting a claim against us governed by the internal affairs doctrine. Our restated bylaws provide that the federal district courts of the United States will be the exclusive forum for any complaint asserting a cause of action arising under the Securities Act of 1933, as amended, or the Securities Act.

Transfer Agent and Registrar

The transfer agent and registrar for the Company’s common stock is Computershare Trust Company, N.A. The transfer agent’s address is 250 Royall Street, Canton, Massachusetts 02021. The transfer agent for any series of preferred stock that we may offer under this prospectus will be named and described in the applicable prospectus supplement related to that series.

Listing

Our common stock is listed on the NYSE American under the symbol “SENS.” The applicable prospectus supplement will contain information, where applicable, as to any other listing, if any, on the NYSE American or any securities market or other exchange of the preferred stock covered by such prospectus supplement.

TABLE OF CONTENTS

DESCRIPTION OF DEBT SECURITIES

We may issue debt securities from time to time, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. While the terms we have summarized below will apply generally to any debt securities that we may offer under this prospectus, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement. The terms of any debt securities offered under a prospectus supplement may differ from the terms described below. Unless the context requires otherwise, whenever we refer to the indenture, we also are referring to any supplemental indentures that specify the terms of a particular series of debt securities.

We will issue the debt securities under the indenture that we will enter into with the trustee named in the indenture. The indenture will be qualified under the Trust Indenture Act of 1939, as amended, or the Trust Indenture Act. We have filed the form of indenture as an exhibit to the registration statement of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of the debt securities being offered will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from reports that we file with the SEC.

The following summary of material provisions of the debt securities and the indenture is subject to, and qualified in its entirety by reference to, all of the provisions of the indenture applicable to a particular series of debt securities. We urge you to read the applicable prospectus supplements and any related free writing prospectuses related to the debt securities that we may offer under this prospectus, as well as the complete indenture that contains the terms of the debt securities.

General

The indenture does not limit the amount of debt securities that we may issue. It provides that we may issue debt securities up to the principal amount that we may authorize and may be in any currency or currency unit that we may designate. Except for the limitations on consolidation, merger and sale of all or substantially all of our assets contained in the indenture, the terms of the indenture do not contain any covenants or other provisions designed to give holders of any debt securities protection against changes in our operations, financial condition or transactions involving us.

We may issue the debt securities issued under the indenture as “discount securities,” which means they may be sold at a discount below their stated principal amount. These debt securities, as well as other debt securities that are not issued at a discount, may be issued with “original issue discount,” or OID, for U.S. federal income tax purposes because of interest payment and other characteristics or terms of the debt securities. Material U.S. federal income tax considerations applicable to debt securities issued with OID will be described in more detail in any applicable prospectus supplement.

We will describe in the applicable prospectus supplement the terms of the series of debt securities being offered, including:

•

the title of the series of debt securities;

•

any limit upon the aggregate principal amount that may be issued;

•

the maturity date or dates;

•

the form of the debt securities of the series;

•

the applicability of any guarantees;

•

whether or not the debt securities will be secured or unsecured, and the terms of any secured debt;

•

whether the debt securities rank as senior debt, senior subordinated debt, subordinated debt or any combination thereof, and the terms of any subordination;

•

if the price (expressed as a percentage of the aggregate principal amount thereof) at which such debt securities will be issued is a price other than the principal amount thereof, the portion of the principal amount thereof payable upon declaration of acceleration of the maturity thereof, or if applicable, the portion of the principal amount of such debt securities that is convertible into another security or the method by which any such portion shall be determined;

TABLE OF CONTENTS

•

the interest rate or rates, which may be fixed or variable, or the method for determining the rate and the date interest will begin to accrue, the dates interest will be payable and the regular record dates for interest payment dates or the method for determining such dates;

•

our right, if any, to defer payment of interest and the maximum length of any such deferral period;

•

if applicable, the date or dates after which, or the period or periods during which, and the price or prices at which, we may, at our option, redeem the series of debt securities pursuant to any optional or provisional redemption provisions and the terms of those redemption provisions;

•

the date or dates, if any, on which, and the price or prices at which we are obligated, pursuant to any mandatory sinking fund or analogous fund provisions or otherwise, to redeem, or at the holder’s option to purchase, the series of debt securities and the currency or currency unit in which the debt securities are payable;

•

the denominations in which we will issue the series of debt securities, if other than denominations of $1,000 and any integral multiple thereof;

•

any and all terms, if applicable, relating to any auction or remarketing of the debt securities of that series and any security for our obligations with respect to such debt securities and any other terms which may be advisable in connection with the marketing of debt securities of that series;

•

whether the debt securities of the series shall be issued in whole or in part in the form of a global security or securities;

•

the terms and conditions, if any, upon which such global security or securities may be exchanged in whole or in part for other individual securities, and the depositary for such global security or securities;

•

if applicable, the provisions relating to conversion or exchange of any debt securities of the series and the terms and conditions upon which such debt securities will be so convertible or exchangeable, including the conversion or exchange price, as applicable, or how it will be calculated and may be adjusted, any mandatory or optional (at our option or the holders’ option) conversion or exchange features, the applicable conversion or exchange period and the manner of settlement for any conversion or exchange;

•

if other than the full principal amount thereof, the portion of the principal amount of debt securities of the series which shall be payable upon declaration of acceleration of the maturity thereof;

•

additions to or changes in the covenants applicable to the particular debt securities being issued, including, among others, the consolidation, merger or sale covenant;

•

additions to or changes in the events of default with respect to the securities and any change in the right of the trustee or the holders to declare the principal, premium, if any, and interest, if any, with respect to such securities to be due and payable;

•

additions to or changes in or deletions of the provisions relating to covenant defeasance and legal defeasance;

•

additions to or changes in the provisions relating to satisfaction and discharge of the indenture;

•

additions to or changes in the provisions relating to the modification of the indenture both with and without the consent of holders of debt securities issued under the indenture;

•

the currency of payment of debt securities if other than U.S. dollars and the manner of determining the equivalent amount in U.S. dollars;

•

whether interest will be payable in cash or additional debt securities at our or the holders’ option and the terms and conditions upon which the election may be made;

•

the terms and conditions, if any, upon which we will pay amounts in addition to the stated interest, premium, if any, and principal amounts of the debt securities of the series to any holder that is not a “United States person” for federal tax purposes;

•

any restrictions on transfer, sale or assignment of the debt securities of the series; and

TABLE OF CONTENTS

•

any other specific terms, preferences, rights or limitations of, or restrictions on, the debt securities, any other additions or changes in the provisions of the indenture, and any terms that may be required by us or advisable under applicable laws or regulations.

Conversion or Exchange Rights

We will set forth in the applicable prospectus supplement the terms on which a series of debt securities may be convertible into or exchangeable for our common stock or our other securities. We will include provisions as to settlement upon conversion or exchange and whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of our common stock or our other securities that the holders of the series of debt securities receive would be subject to adjustment.

Consolidation, Merger or Sale

Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the indenture will not contain any covenant that restricts our ability to merge or consolidate, or sell, convey, transfer or otherwise dispose of our assets as an entirety or substantially as an entirety. However, any successor to or acquirer of such assets (other than a subsidiary of ours) must assume all of our obligations under the indenture or the debt securities, as appropriate.

Events of Default under the Indenture

Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the following are events of default under the indenture with respect to any series of debt securities that we may issue:

•

if we fail to pay any installment of interest on any series of debt securities, as and when the same shall become due and payable, and such default continues for a period of 90 days; provided, however, that a valid extension of an interest payment period by us in accordance with the terms of any indenture supplemental thereto shall not constitute a default in the payment of interest for this purpose;

•

if we fail to pay the principal of, or premium, if any, on any series of debt securities as and when the same shall become due and payable whether at maturity, upon redemption, by declaration or otherwise, or in any payment required by any sinking or analogous fund established with respect to such series; provided, however, that a valid extension of the maturity of such debt securities in accordance with the terms of any indenture supplemental thereto shall not constitute a default in the payment of principal or premium, if any;

•

if we fail to observe or perform any other covenant or agreement contained in the debt securities or the indenture, other than a covenant specifically relating to another series of debt securities, and our failure continues for 90 days after we receive written notice of such failure, requiring the same to be remedied and stating that such is a notice of default thereunder, from the trustee or holders of at least 25% in aggregate principal amount of the outstanding debt securities of the applicable series; and

•

if specified events of bankruptcy, insolvency or reorganization occur.

If an event of default with respect to debt securities of any series occurs and is continuing, other than an event of default specified in the last bullet point above, the trustee or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series, by notice to us in writing, and to the trustee if notice is given by such holders, may declare the unpaid principal, premium, if any, and accrued interest, if any, due and payable immediately. If an event of default specified in the last bullet point above occurs with respect to us, the principal amount of and accrued interest, if any, of each issue of debt securities then outstanding shall be due and payable without any notice or other action on the part of the trustee or any holder.

The holders of a majority in principal amount of the outstanding debt securities of an affected series may waive any default or event of default with respect to the series and its consequences, except defaults or

TABLE OF CONTENTS

events of default regarding payment of principal, premium, if any, or interest, unless we have cured the default or event of default in accordance with the indenture. Any waiver shall cure the default or event of default.

Subject to the terms of the indenture, if an event of default under an indenture shall occur and be continuing, the trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the applicable series of debt securities, unless such holders have offered the trustee reasonable indemnity. The holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the debt securities of that series, provided that:

•

the direction so given by the holder is not in conflict with any law or the applicable indenture; and

•

subject to its duties under the Trust Indenture Act, the trustee need not take any action that might involve it in personal liability or might be unduly prejudicial to the holders not involved in the proceeding.

A holder of the debt securities of any series will have the right to institute a proceeding under the indenture or to appoint a receiver or trustee, or to seek other remedies only if:

•

the holder has given written notice to the trustee of a continuing event of default with respect to that series;

•

the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series have made written request,

•

such holders have offered to the trustee indemnity satisfactory to it against the costs, expenses and liabilities to be incurred by the trustee in compliance with the request; and

•

the trustee does not institute the proceeding, and does not receive from the holders of a majority in aggregate principal amount of the outstanding debt securities of that series other conflicting directions within 90 days after the notice, request and offer.

These limitations do not apply to a suit instituted by a holder of debt securities if we default in the payment of the principal, premium, if any, or interest on, the debt securities.

We will periodically file statements with the trustee regarding our compliance with specified covenants in the indenture.

Modification of Indenture; Waiver

We and the trustee may change an indenture without the consent of any holders with respect to specific matters:

•

to cure any ambiguity, defect or inconsistency in the indenture or in the debt securities of any series;

•

to comply with the provisions described above under “Description of Debt Securities — Consolidation, Merger or Sale;”

•

to provide for uncertificated debt securities in addition to or in place of certificated debt securities;

•

to add to our covenants, restrictions, conditions or provisions such new covenants, restrictions, conditions or provisions for the benefit of the holders of all or any series of debt securities, to make the occurrence, or the occurrence and the continuance, of a default in any such additional covenants, restrictions, conditions or provisions an event of default or to surrender any right or power conferred upon us in the indenture;

•

to add to, delete from or revise the conditions, limitations, and restrictions on the authorized amount, terms, or purposes of issue, authentication and delivery of debt securities, as set forth in the indenture;

•

to make any change that does not adversely affect the interests of any holder of debt securities of any series in any material respect;

TABLE OF CONTENTS

•

to provide for the issuance of and establish the form and terms and conditions of the debt securities of any series as provided above under “Description of Debt Securities — General” to establish the form of any certifications required to be furnished pursuant to the terms of the indenture or any series of debt securities, or to add to the rights of the holders of any series of debt securities;

•

to evidence and provide for the acceptance of appointment under any indenture by a successor trustee; or

•

to comply with any requirements of the SEC in connection with the qualification of any indenture under the Trust Indenture Act.

In addition, under the indenture, the rights of holders of a series of debt securities may be changed by us and the trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each series that is affected. However, unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, we and the trustee may make the following changes only with the consent of each holder of any outstanding debt securities affected:

•

extending the fixed maturity of any debt securities of any series;

•

reducing the principal amount, reducing the rate of or extending the time of payment of interest, or reducing any premium payable upon the redemption of any series of any debt securities; or

•

reducing the percentage of debt securities, the holders of which are required to consent to any amendment, supplement, modification or waiver.

Discharge

Each indenture provides that we can elect to be discharged from our obligations with respect to one or more series of debt securities, except for specified obligations, including obligations to:

•

provide for payment;

•

replace stolen, lost or mutilated debt securities of the series;

•

pay principal of and premium and interest on any debt securities of the series;

•

maintain paying agencies;

•

hold monies for payment in trust;

•

recover excess money held by the trustee;

•

compensate and indemnify the trustee; and

•

appoint any successor trustee.

In order to exercise our rights to be discharged, we must deposit with the trustee money or government obligations sufficient to pay all the principal of, any premium, if any, and interest on, the debt securities of the series on the dates payments are due.

Form, Exchange and Transfer

We will issue the debt securities of each series only in fully registered form without coupons and, unless we provide otherwise in the applicable prospectus supplement, in denominations of $1,000 and any integral multiple thereof. The indenture provides that we may issue debt securities of a series in temporary or permanent global form and as book-entry securities that will be deposited with, or on behalf of, The Depository Trust Company, or DTC, or another depositary named by us and identified in the applicable prospectus supplement with respect to that series. To the extent the debt securities of a series are issued in global form and as book-entry, a description of terms relating to any book-entry securities will be set forth in the applicable prospectus supplement.

At the option of the holder, subject to the terms of the indenture and the limitations applicable to global securities described in the applicable prospectus supplement, the holder of the debt securities of any

TABLE OF CONTENTS

series can exchange the debt securities for other debt securities of the same series, in any authorized denomination and of like tenor and aggregate principal amount.

Subject to the terms of the indenture and the limitations applicable to global securities set forth in the applicable prospectus supplement, holders of the debt securities may present the debt securities for exchange or for registration of transfer, duly endorsed or with the form of transfer endorsed thereon duly executed if so required by us or the security registrar, at the office of the security registrar or at the office of any transfer agent designated by us for this purpose. Unless otherwise provided in the debt securities that the holder presents for transfer or exchange, we will impose no service charge for any registration of transfer or exchange, but we may require payment of any taxes or other governmental charges.

We will name in the applicable prospectus supplement the security registrar, and any transfer agent in addition to the security registrar, that we initially designate for any debt securities. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the debt securities of each series.

If we elect to redeem the debt securities of any series, we will not be required to:

•

issue, register the transfer of, or exchange any debt securities of that series during a period beginning at the opening of business 15 days before the day of mailing of a notice of redemption of any debt securities that may be selected for redemption and ending at the close of business on the day of the mailing; or

•

register the transfer of or exchange any debt securities so selected for redemption, in whole or in part, except the unredeemed portion of any debt securities we are redeeming in part.

Information Concerning the Trustee

The trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture. Upon an event of default under an indenture, the trustee must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, the trustee is under no obligation to exercise any of the powers given it by the indenture at the request of any holder of debt securities unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur.

Payment and Paying Agents

Unless we otherwise indicate in the applicable prospectus supplement, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest.

We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agents designated by us, except that unless we otherwise indicate in the applicable prospectus supplement, we will make interest payments by check that we will mail to the holder or by wire transfer to certain holders. Unless we otherwise indicate in the applicable prospectus supplement, we will designate the corporate trust office of the trustee as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.

All money we pay to a paying agent or the trustee for the payment of the principal of or any premium or interest on any debt securities that remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the debt security thereafter may look only to us for payment thereof.

TABLE OF CONTENTS

DESCRIPTION OF WARRANTS

The following description, together with the additional information we may include in any applicable prospectus supplement and in any related free writing prospectuses, summarizes the material terms and provisions of the warrants that we may offer under this prospectus, which may consist of warrants to purchase common stock, preferred stock or debt securities and may be issued in one or more series. Warrants may be offered independently or together with common stock, preferred stock or debt securities offered by any prospectus supplement, and may be attached to or separate from those securities. While the terms we have summarized below will apply generally to any warrants that we may offer under this prospectus, we will describe the particular terms of any series of warrants that we may offer in more detail in the applicable prospectus supplement and any applicable free writing prospectus. The terms of any warrants offered under a prospectus supplement may differ from the terms described below. However, no prospectus supplement will fundamentally change the terms that are set forth in this prospectus or offer a security that is not registered and described in this prospectus at the time of its effectiveness.

We have filed forms of the warrant agreements and forms of warrant certificates containing the terms of the warrants that may be offered as exhibits to the registration statement of which this prospectus is a part. We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of warrant agreement, if any, including a form of warrant certificate, that describes the terms of the particular series of warrants we are offering. The following summaries of material provisions of the warrants and the warrant agreements are subject to, and qualified in their entirety by reference to, all the provisions of the warrant agreement and warrant certificate applicable to the particular series of warrants that we may offer under this prospectus. We urge you to read the applicable prospectus supplements related to the particular series of warrants that we may offer under this prospectus, as well as any related free writing prospectuses, and the complete warrant agreements and warrant certificates that contain the terms of the warrants.

General

We will describe in the applicable prospectus supplement the terms relating to a series of warrants being offered, including, to the extent applicable:

•

the title of such securities;

•

the offering price or prices and aggregate number of warrants offered;

•

the currency or currencies for which the warrants may be purchased;

•

if applicable, the designation and terms of the securities with which the warrants are issued and the number of warrants issued with each such security or each principal amount of such security;

•

if applicable, the date on and after which the warrants and the related securities will be separately transferable;

•

if applicable, the minimum or maximum amount of such warrants which may be exercised at any one time;

•

in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon exercise of one warrant and the price at which, and currency in which, this principal amount of debt securities may be purchased upon such exercise;

•

in the case of warrants to purchase common stock or preferred stock, the number of shares of common stock or preferred stock, as the case may be, purchasable upon the exercise of one warrant and the price at which, and the currency in which, these shares may be purchased upon such exercise;

•

the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreements and the warrants;

•

the terms of any rights to redeem or call the warrants;

•

the terms of any rights to force the exercise of the warrants;

TABLE OF CONTENTS

•

any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;

•

the dates on which the right to exercise the warrants will commence and expire;

•

the manner in which the warrant agreements and warrants may be modified;

•

a discussion of any material or special U.S. federal income tax consequences of holding or exercising the warrants;

•

the terms of the securities issuable upon exercise of the warrants; and

•

any other specific terms, preferences, rights or limitations of or restrictions on the warrants.

Before exercising their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including:

•

in the case of warrants to purchase debt securities, the right to receive payments of principal of, or interest premium, if any, or interest on, the debt securities purchasable upon exercise or to enforce covenants in the applicable indenture; or

•

in the case of warrants to purchase common stock or preferred stock, the right to receive dividends, if any, or payments upon our liquidation, dissolution, or winding up, or to exercise voting rights, if any.

Exercise of Warrants

Each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to the specified time on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.

Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants by delivering the warrant certificate representing the warrants to be exercised together with specified information, and paying the required amount to the warrant agent in immediately available funds, as provided in the applicable prospectus supplement. We will set forth on the reverse side of the warrant certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent in connection with the exercise of the warrant.

Upon receipt of the required payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the securities purchasable upon such exercise. If fewer than all of the warrants represented by the warrant certificate are exercised, then we will issue a new warrant certificate for the remaining amount of warrants. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for warrants.

Governing Law

Unless we provide otherwise in the applicable prospectus supplement, the warrants and warrant agreements, and any claim, controversy or dispute arising under or related to the warrants or warrant agreements, will be governed by and construed in accordance with the laws of the State of New York.

Enforceability of Rights by Holders of Warrants

Each warrant agent will act solely as our agent under the applicable warrant agreement and will not assume any obligation or relationship of agency or trust with any holder of any warrant. A single bank or trust company may act as warrant agent for more than one issue of warrants. A warrant agent will have no duty or responsibility in case of any default by us under the applicable warrant agreement or warrant, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a warrant may, without the consent of the related warrant agent or the holder of any other warrant, enforce by appropriate legal action its right to exercise, and receive the securities purchasable upon exercise of, its warrants.

TABLE OF CONTENTS

LEGAL OWNERSHIP OF SECURITIES

We can issue securities in registered form or in the form of one or more global securities. We describe global securities in greater detail below. We refer to those persons who have securities registered in their own names on the books that we or any applicable trustee, depositary or warrant agent maintain for this purpose as the “holders” of those securities. These persons are the legal holders of the securities. We refer to those persons who, indirectly through others, own beneficial interests in securities that are not registered in their own names, as “indirect holders” of those securities. As we discuss below, indirect holders are not legal holders, and investors in securities issued in book-entry form or in street name will be indirect holders.

Book-Entry Holders

We may issue securities in book-entry form only, as we will specify in the applicable prospectus supplement. This means securities may be represented by one or more global securities registered in the name of a financial institution that holds them as depositary on behalf of other financial institutions that participate in the depositary’s book-entry system. These participating institutions, which are referred to as participants, in turn, hold beneficial interests in the securities on behalf of themselves or their customers.

Only the person in whose name a security is registered is recognized as the holder of that security. Global securities will be registered in the name of the depositary or its participants. Consequently, for global securities, we will recognize only the depositary as the holder of the securities, and we will make all payments on the securities to the depositary. The depositary passes along the payments it receives to its participants, which in turn pass the payments along to their customers who are the beneficial owners. The depositary and its participants do so under agreements they have made with one another or with their customers; they are not obligated to do so under the terms of the securities.

As a result, investors in a global security will not own securities directly. Instead, they will own beneficial interests in a global security, through a bank, broker or other financial institution that participates in the depositary’s book-entry system or holds an interest through a participant. As long as the securities are issued in global form, investors will be indirect holders, and not legal holders, of the securities.

Street Name Holders

We may terminate a global security or issue securities that are not issued in global form. In these cases, investors may choose to hold their securities in their own names or in “street name.” Securities held by an investor in street name would be registered in the name of a bank, broker or other financial institution that the investor chooses, and the investor would hold only a beneficial interest in those securities through an account he or she maintains at that institution.

For securities held in street name, we or any applicable trustee or depositary will recognize only the intermediary banks, brokers and other financial institutions in whose names the securities are registered as the holders of those securities, and we or any such trustee or depositary will make all payments on those securities to them. These institutions pass along the payments they receive to their customers who are the beneficial owners, but only because they agree to do so in their customer agreements or because they are legally required to do so. Investors who hold securities in street name will be indirect holders, not legal holders, of those securities.

Legal Holders

Our obligations, as well as the obligations of any applicable trustee or third party employed by us or a trustee, run only to the legal holders of the securities. We do not have obligations to investors who hold beneficial interests in global securities, in street name or by any other indirect means. This will be the case whether an investor chooses to be an indirect holder of a security or has no choice because we are issuing the securities only in global form.

For example, once we make a payment or give a notice to the holder, we have no further responsibility for the payment or notice even if that holder is required, under agreements with its participants or customers or by law, to pass it along to the indirect holders but does not do so. Similarly, we may want to obtain the approval of the holders to amend an indenture, to relieve us of the consequences of a default or of our

TABLE OF CONTENTS

obligation to comply with a particular provision of an indenture, or for other purposes. In such an event, we would seek approval only from the holders, and not the indirect holders, of the securities. Whether and how the legal holders contact the indirect holders is up to the legal holders.

Special Considerations for Indirect Holders

If you hold securities through a bank, broker or other financial institution, either in book-entry form because the securities are represented by one or more global securities or in street name, you should check with your own institution to find out:

•

how it handles securities payments and notices;

•

whether it imposes fees or charges;

•

how it would handle a request for the holders’ consent, if ever required;

•

whether and how you can instruct it to send you securities registered in your own name so you can be a holder, if that is permitted in the future;

•

how it would exercise rights under the securities if there were a default or other event triggering the need for holders to act to protect their interests; and

•

if the securities are in book-entry form, how the depositary’s rules and procedures will affect these matters.

Global Securities

A global security is a security that represents one or any other number of individual securities held by a depositary. Generally, all securities represented by the same global securities will have the same terms.

Each security issued in book-entry form will be represented by a global security that we issue to, deposit with and register in the name of a financial institution or its nominee that we select. The financial institution that we select for this purpose is called the depositary. Unless we specify otherwise in the applicable prospectus supplement, all securities issued in book-entry form will be deposited with, or on behalf of, Depository Trust Company, New York, New York, or the DTC, and registered in the name of Cede & Co., the nominee of DTC. A global security may not be transferred to or registered in the name of anyone other than the depositary, its nominee or a successor depositary, unless special termination situations arise. We describe those situations below under “— Special Situations When a Global Security Will Be Terminated.” As a result of these arrangements, the depositary, or its nominee, will be the sole registered owner and legal holder of all securities represented by a global security, and investors will be permitted to own only beneficial interests in a global security. Beneficial interests must be held by means of an account with a broker, bank or other financial institution that in turn has an account with the depositary or with another institution that does. Thus, an investor whose security is represented by a global security will not be a legal holder of the security, but only an indirect holder of a beneficial interest in the global security.

If the prospectus supplement for a particular security indicates that the security will be issued as a global security, then the security will be represented by a global security at all times unless and until the global security is terminated. If termination occurs, we may issue the securities through another book-entry clearing system or decide that the securities may no longer be held through any book-entry clearing system.

Special Considerations for Global Securities

As an indirect holder, an investor’s rights relating to a global security will be governed by the account rules of the investor’s financial institution and of the depositary, as well as general laws relating to securities transfers. We do not recognize an indirect holder as a holder of securities and instead deal only with the depositary that holds the global security.

If securities are issued only as global securities, an investor should be aware of the following:

•

an investor cannot cause the securities to be registered in his or her name, and cannot obtain non-global certificates for his or her interest in the securities, except in the special situations we describe below;

TABLE OF CONTENTS

•

an investor will be an indirect holder and must look to his or her own bank or broker for payments on the securities and protection of his or her legal rights relating to the securities, as we describe above;

•

an investor may not be able to sell interests in the securities to some insurance companies and to other institutions that are required by law to own their securities in non-book-entry form;

•

an investor may not be able to pledge his or her interest in the global security in circumstances where certificates representing the securities must be delivered to the lender or other beneficiary of the pledge in order for the pledge to be effective;

•

the depositary’s policies, which may change from time to time, will govern payments, transfers, exchanges and other matters relating to an investor’s interest in the global security;

•

we and any applicable trustee have no responsibility for any aspect of the depositary’s actions or for its records of ownership interests in the global security, nor will we or any applicable trustee supervise the depositary in any way;

•

the depositary may, and we understand that DTC will, require that those who purchase and sell interests in the global security within its book-entry system use immediately available funds, and your broker or bank may require you to do so as well; and

•

financial institutions that participate in the depositary’s book-entry system, and through which an investor holds its interest in the global security, may also have their own policies affecting payments, notices and other matters relating to the securities.

There may be more than one financial intermediary in the chain of ownership for an investor. We do not monitor and are not responsible for the actions of any of those intermediaries.

Special Situations When a Global Security Will Be Terminated

In a few special situations described below, a global security will terminate and interests in it will be exchanged for physical certificates representing those interests. After that exchange, the choice of whether to hold securities directly or in street name will be up to the investor. Investors must consult their own banks or brokers to find out how to have their interests in securities transferred to their own names, so that they will be direct holders. We have described the rights of holders and street name investors above.

A global security will terminate when the following special situations occur:

•

if the depositary notifies us that it is unwilling, unable or no longer qualified to continue as depositary for that global security and we do not appoint another institution to act as depositary within 90 days;

•

if we notify any applicable trustee that we wish to terminate that global security; or

•

if an event of default has occurred with regard to securities represented by that global security and has not been cured or waived.

The applicable prospectus supplement may also list additional situations for terminating a global security that would apply only to the particular series of securities covered by the prospectus supplement. When a global security terminates, the depositary, and neither we nor any applicable trustee, is responsible for deciding the names of the institutions that will be the initial direct holders.

TABLE OF CONTENTS

PLAN OF DISTRIBUTION

We may sell the securities covered hereby from time to time pursuant to underwritten public offerings, direct sales to the public, negotiated transactions, block trades or a combination of these methods. A distribution of these securities offered by this prospectus may also be effected through the issuance of derivative securities, including without limitation, warrants. We may directly solicit offers to purchase securities, or agents may be designated to solicit such offers, we may also sell the securities to or through underwriters or dealers, through agents, directly to one or more purchasers, or through a combination of any of these methods of sale. We may distribute securities from time to time in one or more transactions:

•

at a fixed price or prices, which may be changed;

•

at market prices prevailing at the time of sale;

•

at prices related to such prevailing market prices; or

•

at negotiated prices.

We may also sell equity securities covered by this registration statement in an “at the market offering” as defined in Rule 415(a)(4) under the Securities Act. Such offering may be made into an existing trading market for such securities in transactions at other than a fixed price, either:

•

on or through the facilities of the NYSE American or any other securities exchange or quotation or trading service on which such securities may be listed, quoted, or traded at the time of sale; and/or

•

to or through a market maker other than on the NYSE American or such other securities exchanges or quotation or trading services.

Such “at-the-market offerings,” if any, may be conducted by underwriters acting as principal or agent.

A prospectus supplement or supplements (and any related free writing prospectus that we may authorize to be provided to you) will describe the terms of the offering of the securities, including, to the extent applicable:

•

the terms of the offering;

•

the name or names of any underwriters, dealers or agents, if any;

•

the name or names of any managing underwriter or underwriters, if any;

•

the amounts of securities underwritten or purchased by each of them;

•

the purchase price of the securities or other consideration therefor and the proceeds, if any, we will receive from the sale;

•

any over-allotment options under which underwriters may purchase additional securities from us;

•

any agency fees or underwriting discounts, concessions, commissions, and other items constituting agents’ or underwriters’ compensation;

•

any delayed delivery arrangements;

•

any public offering price;

•

any discounts or concessions allowed or reallowed or paid to dealers; and

•

any securities exchange or market on which the securities may be listed.

Only underwriters named in the prospectus supplement are underwriters of the securities offered by the prospectus supplement. Dealers and agents participating in the distribution of the securities may be deemed to be underwriters, and compensation received by them on resale of the securities may be deemed to be underwriting discounts. If such dealers or agents were deemed to be underwriters, they may be subject to statutory liabilities under the Securities Act.

If underwriters are used in the sale, they will acquire the securities for their own account and may resell the securities from time to time in one or more transactions at a fixed public offering price or at varying prices

TABLE OF CONTENTS

determined at the time of sale. The obligations of the underwriters to purchase the securities will be subject to the conditions set forth in the applicable underwriting agreement. We may offer the securities to the public through underwriting syndicates represented by managing underwriters or by underwriters without a syndicate. Subject to certain conditions, the underwriters will be obligated to purchase all of the securities offered by the applicable prospectus supplement, other than securities covered by any option to purchase additional securities. If a dealer is used in the sale of securities, we or an underwriter will sell the securities to the dealer, as principal. The dealer may then resell the securities to the public at varying prices to be determined by the dealer at the time of resale. To the extent required, we will set forth in the prospectus supplement the name of the dealer and the terms of the transaction. Any public offering price and any discounts or concessions allowed or re-allowed or paid to dealers may change from time to time. We may use underwriters with whom we have a material relationship. We will describe in the prospectus supplement that names the underwriter the nature of any such relationship.

We may sell securities directly or through agents we designate from time to time. In the prospectus supplement, we will name any agent involved in the offering and sale of securities and describe any commissions and other compensation we will pay the agent. Unless the prospectus supplement states otherwise, our agent will act on a best-efforts basis for the period of its appointment.

We may authorize agents or underwriters to solicit offers by certain types of institutional investors to purchase securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. We will describe in the prospectus supplement the conditions to these contracts and the commissions we must pay for solicitation of these contracts.

We may provide agents, underwriters, and dealers with indemnification against civil liabilities related to this offering, including liabilities under the Securities Act, or contribution with respect to payments that the agents, underwriters, or dealers may make with respect to these liabilities. Agents, underwriters, and dealers, or their affiliates, may engage in transactions with, or perform services for, us in the ordinary course of business.

Unless the applicable prospectus supplement states otherwise, all securities we offer, other than common stock, will be new issues of securities with no established trading market. Any agents or underwriters may make a market in these securities but will not be obligated to do so and may discontinue any market making at any time without notice. We cannot guarantee the liquidity of the trading markets for any securities. There is currently no market for any of the offered securities, other than our common stock which is listed on the NYSE American. We have no current plans for listing of the preferred stock, debt securities or warrants on any securities exchange or quotation system; any such listing with respect to any particular preferred stock, debt securities or warrants will be described in the applicable prospectus supplement or other offering materials, as the case may be.

Any agents and underwriter may engage in overallotment, stabilizing transactions, short covering transactions and penalty bids in accordance with Rule 103 of Regulation M under the Securities Exchange Act of 1934, as amended, or the Exchange Act. Overallotment involves sales in excess of the offering size, which create a short position. Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum. Short covering transactions involve purchases of the securities in the open market after the distribution is completed to cover short positions. Penalty bids permit the underwriters to reclaim a selling concession from a dealer when the securities originally sold by the dealer are purchased in a stabilizing or covering transaction to cover short positions. Those activities may cause the price of the securities to be higher than it would otherwise be. If commenced, the underwriters may discontinue any of the activities at any time. These transactions may be effected on any exchange or over-the-counter market or otherwise.

Any underwriters who are qualified market makers on the NYSE American may engage in passive market-making transactions in the securities on the NYSE American in accordance with Rule 103 of Regulation M during the business day prior to the pricing of the offering, before the commencement of offers or sales of the securities. Passive market makers must comply with applicable volume and price limitations and must be identified as passive market makers. In general, a passive market maker must display its bid at a price not in excess of the highest independent bid for such security; if all independent bids are lowered below the passive

TABLE OF CONTENTS

LEGAL MATTERS

Cooley LLP will pass upon the validity of the securities offered by this prospectus, and any supplement thereto, unless otherwise indicated in the applicable prospectus supplement. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we will name in the applicable prospectus supplement.

EXPERTS

The consolidated financial statements of Senseonics Holdings, Inc. and its subsidiaries as of December 31, 2024 and 2023 and for each of the years in the two-year period ended December 31, 2024 have been incorporated by reference in this prospectus herein in reliance upon the report of KPMG LLP, an independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

The audit report covering the December 31, 2024 consolidated financial statements contain an explanatory paragraph that states that the Company’s current operating plan, existing unrestricted cash, and cash equivalents, and minimum cash and satisfaction of performance milestones to comply with debt covenants under its Loan and Security Agreement raise substantial doubt about the entity’s ability to continue as a going concern. The consolidated financial statements do not include any adjustments that might result from the outcome of that uncertainty.

WHERE YOU CAN FIND ADDITIONAL INFORMATION

This prospectus is part of the registration statement on Form S-3 we filed with the SEC under the Securities Act and does not contain all the information set forth in the registration statement. Whenever a reference is made in this prospectus to any of our contracts, agreements or other documents, the reference may not be complete and you should refer to the exhibits that are a part of the registration statement or the exhibits to the reports or other documents incorporated by reference into this prospectus for a copy of such contract, agreement or other document. Because we are subject to the information and reporting requirements of the Exchange Act, we file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s website at http://www.sec.gov. In addition, we maintain a website that contains information about us at www.senseonics.com. The information found on, or otherwise accessible through our website is not incorporated by reference into, and does not form a part of, this prospectus or any accompanying prospectus supplement or any other document or report we file or furnish with the SEC.

TABLE OF CONTENTS

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to incorporate by reference information from other documents that we file with it, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus. Information in this prospectus supersedes information incorporated by reference that we filed with the SEC prior to the date of this prospectus, while information that we file later with the SEC will automatically update and supersede the information in this prospectus. We incorporate by reference into this prospectus and the registration statement of which this prospectus is a part the information or documents listed below that we have filed with the SEC:

•

our Annual Report on Form 10-K for the year ended December 31, 2024, filed with the SEC on March 3, 2025;

•

our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2025 and June 30, 2025, filed with the SEC on May 8, 2025 and August 6, 2025, respectively;

•

our Current Reports on Form 8-K filed with the SEC on January 13, 2025, January 17, 2025, May 15, 2025, May 16, 2025, May 19, 2025, and May 21, 2025 (each to the extent the information in such reports is filed and not furnished); and

•

our Definitive Proxy Statement on Schedule 14A, filed with the SEC on April 10, 2025 (other than the portions that are not required to be incorporated by reference into our Annual Report on Form 10-K for the year ended December 31, 2024);

•

the description of our common stock contained in our registration statement on Form 8-A, filed with the SEC on March 11, 2016, as updated by Exhibit 4.3 of our Annual Report on Form 10-K for the year ended December 31, 2024, filed with the SEC on March 3, 2025, including any amendments or reports filed for the purpose of updating such description.

We also incorporate by reference any future filings (other than current reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits filed on such form that are related to such items unless such Form 8-K expressly provides to the contrary) made with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, including those made after the date of the initial filing of the registration statement of which this prospectus is a part and prior to effectiveness of such registration statement, and after the date of this prospectus until we file a post-effective amendment that indicates the termination of the offering of the securities made by this prospectus, which will become a part of this prospectus from the date that such documents are filed with the SEC. Information in such future filings updates and supplements the information provided in this prospectus. Any statements in any such future filings will automatically be deemed to modify and supersede any information in any document we previously filed with the SEC that is incorporated or deemed to be incorporated herein by reference to the extent that statements in the later-filed document modify or replace such earlier statements. We will furnish without charge to each person, including any beneficial owner, to whom a prospectus is delivered, upon written or oral request, a copy of any or all of the documents incorporated by reference into this prospectus but not delivered with the prospectus, including exhibits that are specifically incorporated by reference into such documents. You should direct any requests for documents to:

Senseonics Holdings, Inc.
Attn: Investor Relations
20451 Seneca Meadows Parkway
Germantown, MD
20876-7005
Telephone: (301) 515-7260.

Our SEC filings are available to the public over the Internet at the SEC’s website at http://www.sec.gov. You may also access these documents on our website, www.senseonics.com. The information contained on this website is not a part of this prospectus.

We have not authorized anyone to provide you with information different from or in addition to that contained or incorporated by reference in this prospectus. We are not making any offer of these securities in any jurisdiction where the offer is not permitted. You should not assume that the information in this prospectus is accurate as of any date other than the date on the front of those documents.

	Page
ABOUT THIS PROSPECTUS		1
PROSPECTUS SUMMARY		3
RISK FACTORS		7
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS		8
USE OF PROCEEDS		10
DESCRIPTION OF CAPITAL STOCK		11
DESCRIPTION OF DEBT SECURITIES		14
DESCRIPTION OF WARRANTS		21
LEGAL OWNERSHIP OF SECURITIES		23
PLAN OF DISTRIBUTION		26
LEGAL MATTERS		29
EXPERTS		29
WHERE YOU CAN FIND ADDITIONAL INFORMATION		29
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE		30