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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 14A

PROXY STATEMENT PURSUANT TO SECTION 14(A) OF
THE SECURITIES EXCHANGE ACT OF 1934

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Marketo, Inc.
901 Mariners Island Blvd., Suite 500
San Mateo, CA 94404

June 29, 2016

Dear Marketo Stockholder:

        You are cordially invited to attend a special meeting (the "Special Meeting") of stockholders of Marketo, Inc. ("Marketo") to be held on July 28, 2016, at Marketo's headquarters, located at 901 Mariners Island Blvd., 1^st Floor, San Mateo, CA 94404, at 2:30 p.m. Pacific time.

        At the Special Meeting, you will be asked to consider and vote on a proposal to adopt the Agreement and Plan of Merger, dated May 27, 2016, as it may be amended from time to time (the "Merger Agreement"), by and among Marketo, Milestone Holdco, LLC ("Parent"), and Milestone Merger Sub, Inc. ("Merger Sub"). Parent and Merger Sub are entities that are affiliated with Vista Equity Partners Management, LLC, a leading private equity firm focused on investments in software, data and technology-enabled companies. Pursuant to the terms of the Merger Agreement, Merger Sub will merge with and into Marketo, with Marketo continuing as the surviving corporation and a wholly owned direct subsidiary of Parent (the "Merger").

        If the Merger is completed, you will be entitled to receive $35.25 in cash, without interest thereon and less any applicable withholding taxes, for each share of common stock that you own (unless you have properly exercised your appraisal rights), which represents a premium of approximately: (1) 64% to the unaffected closing price of Marketo's common stock on May 9, 2016, the last full trading day prior to public reports that Marketo engaged Morgan Stanley to explore strategic alternatives, including a potential sale; and (2) 67% to the average closing market price of the common stock for the thirty trading day period ending on May 9, 2016, the last full trading day prior to public reports that Marketo engaged Morgan Stanley to explore strategic alternatives, including a potential sale.

        The Board of Directors, after considering the factors more fully described in the enclosed proxy statement, has unanimously: (1) determined that the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement are fair to, advisable and in the best interests of, Marketo and its stockholders; and (2) adopted and approved the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement. The Board of Directors recommends that you vote: (1) "FOR" the adoption of the Merger Agreement; and (2) "FOR" the adjournment of the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting.

        The enclosed proxy statement provides detailed information about the Special Meeting, the Merger Agreement and the Merger. A copy of the Merger Agreement is attached as Annex A to the proxy statement.

        The proxy statement also describes the actions and determinations of the Board of Directors in connection with its evaluation of the Merger Agreement and the Merger. You should carefully read and consider the entire enclosed proxy statement and its annexes, including, but not limited to, the Merger Agreement, as they contain important information about, among other things, the Merger and how it affects you.

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        Whether or not you plan to attend the Special Meeting in person, please sign, date and return, as promptly as possible, the enclosed proxy card in the accompanying prepaid reply envelope or grant your proxy electronically over the Internet or by telephone (using the instructions provided in the enclosed proxy card). If you attend the Special Meeting and vote in person by ballot, your vote will revoke any proxy that you have previously submitted.

        If you hold your shares in "street name," you should instruct your bank, broker or other nominee how to vote your shares in accordance with the voting instruction form that you will receive from your bank, broker or other nominee. Your bank, broker or other nominee cannot vote on any of the proposals, including the proposal to adopt the Merger Agreement, without your instructions.

        Your vote is very important, regardless of the number of shares that you own. We cannot complete the Merger unless the proposal to adopt the Merger Agreement is approved by the affirmative vote of the holders of at least a majority of the outstanding shares of Marketo's common stock.

        If you have any questions or need assistance voting your shares, please contact our proxy solicitor:

Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, NY 10022
Call toll-free: (888) 750-5834

        On behalf of the Board of Directors, I thank you for your support and appreciate your consideration of this matter.

        The accompanying proxy statement is dated June 29, 2016 and, together with the enclosed form of proxy card, is first being mailed on or about June 29, 2016.

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Marketo, Inc.
901 Mariners Island Blvd., Suite 500
San Mateo, CA 94404

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS
TO BE HELD ON JULY 28, 2016

        Notice is hereby given that a special meeting of stockholders (the "Special Meeting") of Marketo, Inc., a Delaware corporation ("Marketo"), will be held on July 28, 2016, at Marketo's headquarters, located at 901 Mariners Island Blvd., 1^st Floor, San Mateo, CA 94404, at 2:30 p.m. Pacific time, for the following purposes:

        1.     To consider and vote on the proposal to adopt the Agreement and Plan of Merger, dated May 27, 2016, as it may be amended from time to time (the "Merger Agreement"), by and among Marketo, Milestone Holdco, LLC ("Parent"), and Milestone Merger Sub, Inc. ("Merger Sub"). Pursuant to the terms of the Merger Agreement, Merger Sub will merge with and into Marketo, with Marketo continuing as the surviving corporation and a wholly owned direct subsidiary of Parent (the "Merger");

        2.     To consider and vote on any proposal to adjourn the Special Meeting to a later date or dates if necessary or appropriate to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting; and

        3.     To transact any other business that may properly come before the Special Meeting or any adjournment, postponement or other delay of the Special Meeting.

        Only stockholders of record as of the close of business on June 28, 2016, are entitled to notice of the Special Meeting and to vote at the Special Meeting or any adjournment, postponement or other delay thereof.

        The Board of Directors unanimously recommends that you vote: (1) "FOR" the adoption of the Merger Agreement; and (2) "FOR" the adjournment of the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting.

        Whether or not you plan to attend the Special Meeting in person, please sign, date and return, as promptly as possible, the enclosed proxy card in the accompanying prepaid reply envelope or grant your proxy electronically over the Internet or by telephone (using the instructions provided in the enclosed proxy card). If you attend the Special Meeting and vote in person by ballot, your vote will revoke any proxy that you have previously submitted. If you hold your shares in "street name," you should instruct your bank, broker or other nominee how to vote your shares in accordance with the voting instruction form that you will receive from your bank, broker or other nominee. Your bank, broker or other nominee cannot vote on any of the proposals, including the proposal to adopt the Merger Agreement, without your instructions.

Dated: June 29, 2016

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YOUR VOTE IS IMPORTANT

        WHETHER OR NOT YOU PLAN TO ATTEND THE SPECIAL MEETING IN PERSON, WE ENCOURAGE YOU TO SUBMIT YOUR PROXY AS PROMPTLY AS POSSIBLE: (1) BY TELEPHONE; (2) THROUGH THE INTERNET; OR (3) BY SIGNING AND DATING THE ENCLOSED PROXY CARD AND RETURNING IT IN THE POSTAGE-PAID ENVELOPE PROVIDED. You may revoke your proxy or change your vote at any time before it is voted at the Special Meeting.

        If you hold your shares in "street name," you should instruct your bank, broker or other nominee how to vote your shares in accordance with the voting instruction form that you will receive from your bank, broker or other nominee. Your broker or other agent cannot vote on any of the proposals, including the proposal to adopt the Merger Agreement, without your instructions.

        If you are a stockholder of record, voting in person by ballot at the Special Meeting will revoke any proxy that you previously submitted. If you hold your shares through a bank, broker or other nominee, you must obtain a "legal proxy" in order to vote in person at the Special Meeting.

        If you fail to (1) return your proxy card, (2) grant your proxy electronically over the Internet or by telephone or (3) vote by ballot in person at the Special Meeting, your shares will not be counted for purposes of determining whether a quorum is present at the Special Meeting and, if a quorum is present, will have the same effect as a vote "AGAINST" the proposal to adopt the Merger Agreement, but will have no effect on the adjournment proposal.

        You should carefully read and consider the entire accompanying proxy statement and its annexes, including, but not limited to, the Merger Agreement, along with all of the documents incorporated by reference into the accompanying proxy statement, as they contain important information about, among other things, the Merger and how it affects you. If you have any questions concerning the Merger Agreement, the Merger, the Special Meeting or the accompanying proxy statement, would like additional copies of the accompanying proxy statement or need help voting your shares of common stock, please contact our proxy solicitor:

Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, NY 10022
Call toll-free: (888) 750-5834

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QUESTIONS AND ANSWERS

        The following questions and answers address some commonly asked questions regarding the Merger, the Merger Agreement and the Special Meeting. These questions and answers may not address all questions that are important to you. You should carefully read and consider the more detailed information contained elsewhere in this proxy statement and the annexes to this proxy statement, including, but not limited to, the Merger Agreement, along with all of the documents we refer to in this proxy statement, as they contain important information about, among other things, the Merger and how it affects you. You may obtain the information incorporated by reference in this proxy statement without charge by following the instructions under the caption, "Where You Can Find More Information."

Q:

Why am I receiving these materials?

A:

The Board of Directors is furnishing this proxy statement and form of proxy card to the holders of shares of common stock in connection with the solicitation of proxies to be voted at the Special Meeting.

Q:

What am I being asked to vote on at the Special Meeting?

A:

You are being asked to vote on the following proposals:

•

to adopt the Merger Agreement pursuant to which Merger Sub will merge with and into Marketo, and Marketo will become a wholly owned direct subsidiary of Parent; and

•

to approve the adjournment of the Special Meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting.

Q:

When and where is the Special Meeting?

A:

The Special Meeting will take place on Thursday, July 28, 2016, at Marketo's headquarters, located at 901 Mariners Island Blvd., 1^st Floor, San Mateo, CA 94404, at 2:30 p.m. Pacific time.

Q:

Who is entitled to vote at the Special Meeting?

A:

Stockholders as of the Record Date are entitled to notice of the Special Meeting and to vote at the Special Meeting. Each holder of shares of common stock is entitled to cast one vote on each matter properly brought before the Special Meeting for each share of common stock owned as of the Record Date.

Q:

May I attend the Special Meeting and vote in person?

A:

Yes. All stockholders as of the Record Date may attend the Special Meeting and vote in person. Seating will be limited. Stockholders will need to present proof of ownership of shares of common stock, such as a bank or brokerage account statement, and a form of personal identification to be admitted to the Special Meeting. No cameras, recording equipment, electronic devices, large bags, briefcases or packages will be permitted in the Special Meeting.

Even if you plan to attend the Special Meeting in person, to ensure that your shares will be represented at the Special Meeting we encourage you to sign, date and return the enclosed proxy card in the accompanying prepaid reply envelope or grant your proxy electronically over the Internet or by telephone (using the instructions provided in the enclosed proxy card). If you attend the Special Meeting and vote in person by ballot, your vote will revoke any proxy previously submitted.

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If you hold your shares in "street name," you should instruct your bank, broker or other nominee how to vote your shares in accordance with the voting instruction form that you will receive from your bank, broker or other nominee. Your broker or other agent cannot vote on any of the proposals, including the proposal to adopt the Merger Agreement, without your instructions. If you hold your shares in "street name," you may not vote your shares in person at the Special Meeting unless you obtain a "legal proxy" from your bank, broker or other nominee.

Q:

What is the proposed Merger and what effects will it have on Marketo?

A:

The proposed Merger is the acquisition of Marketo by Parent. If the proposal to adopt the Merger Agreement is approved by stockholders and the other closing conditions under the Merger Agreement have been satisfied or waived, Merger Sub will merge with and into Marketo, with Marketo continuing as the Surviving Corporation. As a result of the Merger, Marketo will become a wholly owned direct subsidiary of Parent, and our common stock will no longer be publicly traded and will be delisted from the NASDAQ. In addition, our common stock will be deregistered under the Exchange Act, and we will no longer file periodic reports with the SEC.

Q:

What will I receive if the Merger is completed?

A:

Upon completion of the Merger, you will be entitled to receive the Per Share Merger Consideration of $35.25 in cash, without interest thereon and less any applicable withholding taxes, for each share of common stock that you own, unless you have properly exercised and not withdrawn your appraisal rights under the DGCL. For example, if you own 100 shares of common stock, you will receive $3,525.00 in cash in exchange for your shares of common stock, less any applicable withholding taxes.

Q:

How does the Per Share Merger Consideration compare to the recent trading price of Marketo common stock?

A:

The Per Share Merger Consideration represents a premium of approximately: (1) 64% to the unaffected closing price of Marketo's common stock on May 9, 2016, the last full trading day prior to public reports that Marketo engaged Morgan Stanley to explore strategic alternatives, including a potential sale; and (2) 67% to the average closing market price of the common stock for the thirty trading day period ending on May 9, 2016, the last full trading day prior to public reports that Marketo engaged Morgan Stanley to explore strategic alternatives, including a potential sale.

Q:

What do I need to do now?

A:

You should carefully read and consider this entire proxy statement and the annexes to this proxy statement, including, but not limited to, the Merger Agreement, along with all of the documents that we refer to in this proxy statement, as they contain important information about, among other things, the Merger and how it affects you. Then sign, date and return, as promptly as possible, the enclosed proxy card in the accompanying reply envelope, or grant your proxy electronically over the Internet or by telephone (using the instructions provided in the enclosed proxy card), so that your shares can be voted at the Special Meeting, unless you wish to seek appraisal. If you hold your shares in "street name," please refer to the voting instruction forms provided by your bank, broker or other nominee to vote your shares.

Q:

Should I surrender my book-entry shares now?

A:

No. After the Merger is completed, the payment agent will send each holder of record a check at such holder's registered address in payment for the shares of common stock represented by such holder's book-entry shares.

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Q:

What happens if I sell or otherwise transfer my shares of common stock after the Record Date but before the Special Meeting?

A:

The Record Date for the Special Meeting is earlier than the date of the Special Meeting and the date the Merger is expected to be completed. If you sell or transfer your shares of common stock after the Record Date but before the Special Meeting, unless special arrangements (such as provision of a proxy) are made between you and the person to whom you sell or otherwise transfer your shares and each of you notifies Marketo in writing of such special arrangements, you will transfer the right to receive the Merger consideration, if the Merger is completed, to the person to whom you sell or transfer your shares, but you will retain your right to vote those shares at the Special Meeting. Even if you sell or otherwise transfer your shares of common stock after the Record Date, we encourage you to sign, date and return the enclosed proxy card in the accompanying reply envelope or grant your proxy electronically over the Internet or by telephone (using the instructions provided in the enclosed proxy card).

Q:

How does the Board of Directors recommend that I vote?

A:

The Board of Directors, after considering the various factors described under the caption, "The Merger—Recommendation of the Board of Directors and Reasons for the Merger," has unanimously: (1) determined that the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement are fair to, advisable and in the best interests of Marketo and its stockholders; and (2) adopted and approved the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement.

The Board of Directors recommends that you vote: (1) "FOR" the adoption of the Merger Agreement; and (2) "FOR" the adjournment of the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting.

Q:

What happens if the Merger is not completed?

A:

If the Merger Agreement is not adopted by stockholders or if the Merger is not completed for any other reason, stockholders will not receive any payment for their shares of common stock. Instead, Marketo will remain an independent public company, our common stock will continue to be listed and traded on the NASDAQ and registered under the Exchange Act, and we will continue to file periodic reports with the SEC.

Under specified circumstances, Marketo will be required to pay Parent a termination fee of $49.2 million upon the termination of the Merger Agreement, as described in the section of this proxy statement captioned, "Proposal 1: Adoption of the Merger Agreement—Termination Fee."

Q:

What vote is required to adopt the Merger Agreement?

A:

The affirmative vote of the holders of a majority of the outstanding shares of common stock is required to adopt the Merger Agreement.

If a quorum is present at the Special Meeting, the failure of any stockholder of record to: (1) submit a signed proxy card; (2) grant a proxy over the Internet or by telephone (using the instructions provided in the enclosed proxy card); or (3) vote in person by ballot at the Special Meeting will have the same effect as a vote "AGAINST" the proposal to adopt the Merger Agreement. If you hold your shares in "street name" and a quorum is present at the Special Meeting, the failure to instruct your bank, broker or other nominee how to vote your shares will have the same effect as a vote "AGAINST" the proposal to adopt the Merger Agreement. If a

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quorum is present at the Special Meeting, abstentions will have the same effect as a vote "AGAINST" the proposal to adopt the Merger Agreement.

Q:

What vote is required to approve any proposal to adjourn the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting?

A:

Approval of the proposal to adjourn the Special Meeting, whether or not a quorum is present, requires the affirmative vote of a majority of the voting power of the shares present in person or represented by proxy and entitled to vote at the Special Meeting.

The failure of any stockholder of record to: (1) submit a signed proxy card; (2) grant a proxy over the Internet or by telephone (using the instructions provided in the enclosed proxy card); or (3) vote in person by ballot at the Special Meeting will not have any effect on the adjournment proposal. If you hold your shares in "street name," the failure to instruct your bank, broker or other nominee how to vote your shares will not have any effect on the adjournment proposal. Abstentions will have the same effect as a vote "AGAINST" the adjournment proposal.

Q:

What is the difference between holding shares as a stockholder of record and as a beneficial owner?

A:

If your shares are registered directly in your name with our transfer agent, Computershare Trust Company, N.A, you are considered, with respect to those shares, to be the "stockholder of record." In this case, this proxy statement and your proxy card have been sent directly to you by Marketo.

If your shares are held through a bank, broker or other nominee, you are considered the "beneficial owner" of shares of common stock held in "street name." In that case, this proxy statement has been forwarded to you by your bank, broker or other nominee who is considered, with respect to those shares, to be the stockholder of record. As the beneficial owner, you have the right to direct your bank, broker or other nominee how to vote your shares by following their instructions for voting. You are also invited to attend the Special Meeting. However, because you are not the stockholder of record, you may not vote your shares in person at the Special Meeting unless you obtain a "legal proxy" from your bank, broker or other nominee.

Q:

How may I vote?

A:

If you are a stockholder of record (that is, if your shares of common stock are registered in your name with Computershare Trust Company, N.A, our transfer agent), there are four ways to vote:

•

by signing, dating and returning the enclosed proxy card in the accompanying prepaid reply envelope;

•

by visiting the Internet at the address on your proxy card;

•

by calling toll-free (within the U.S. or Canada) at the phone number on your proxy card; or

•

by attending the Special Meeting and voting in person by ballot;

A control number, located on your proxy card, is designed to verify your identity and allow you to vote your shares of common stock, and to confirm that your voting instructions have been properly recorded when voting electronically over the Internet or by telephone (using the instructions provided in the enclosed proxy card). Please be aware that, although there is no charge for voting your shares, if you vote electronically over the Internet or by telephone, you may incur costs such as Internet access and telephone charges for which you will be responsible.

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Even if you plan to attend the Special Meeting in person, you are strongly encouraged to vote your shares of common stock by proxy. If you are a record holder or if you obtain a "legal proxy" to vote shares that you beneficially own, you may still vote your shares of common stock in person by ballot at the Special Meeting even if you have previously voted by proxy. If you are present at the Special Meeting and vote in person by ballot, your previous vote by proxy will not be counted.

If your shares are held in "street name" through a bank, broker or other nominee, you may vote through your bank, broker or other nominee by completing and returning the voting form provided by your bank, broker or other nominee, or, if such a service is provided by your bank, broker or other nominee, electronically over the Internet or by telephone. To vote over the Internet or by telephone through your bank, broker or other nominee, you should follow the instructions on the voting form provided by your bank, broker or nominee.

Q:

If my broker holds my shares in "street name," will my broker vote my shares for me?

A:

No. Your bank, broker or other nominee is permitted to vote your shares on any proposal currently scheduled to be considered at the Special Meeting only if you instruct your bank, broker or other nominee how to vote. You should follow the procedures provided by your bank, broker or other nominee to vote your shares. Without instructions, your shares will not be voted on such proposals, which will have the same effect as if you voted against adoption of the Merger Agreement, but will have no effect on the adjournment proposal.

Q:

May I change my vote after I have mailed my signed and dated proxy card?

A:

Yes. If you are a stockholder of record, you may change your vote or revoke your proxy at any time before it is voted at the Special Meeting by:

•

signing another proxy card with a later date and returning it to us prior to the Special Meeting;

•

submitting a new proxy electronically over the Internet or by telephone after the date of the earlier submitted proxy;

•

delivering a written notice of revocation to the Corporate Secretary; or

•

attending the Special Meeting and voting in person by ballot.

If you hold your shares of common stock in "street name," you should contact your bank, broker or other nominee for instructions regarding how to change your vote. You may also vote in person at the Special Meeting if you obtain a "legal proxy" from your bank, broker or other nominee.

Q:

What is a proxy?

A:

A proxy is your legal designation of another person to vote your shares of common stock. The written document describing the matters to be considered and voted on at the Special Meeting is called a "proxy statement." The document used to designate a proxy to vote your shares of common stock is called a "proxy card." Phillip M. Fernandez, our Chairman and Chief Executive Officer, Brian K. Kinion, our Senior Vice President and Chief Financial Officer and Margo M. Smith, our Senior Vice President and General Counsel, are the proxy holders for the Special Meeting.

Q:

If a stockholder gives a proxy, how are the shares voted?

A:

Regardless of the method you choose to vote, the individuals named on the enclosed proxy card, or your proxies, will vote your shares in the way that you indicate. When completing the Internet or telephone process or the proxy card, you may specify whether your shares should be voted for

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or against or to abstain from voting on all, some or none of the specific items of business to come before the Special Meeting.

If you properly sign your proxy card but do not mark the boxes showing how your shares should be voted on a matter, the shares represented by your properly signed proxy will be voted: (1) "FOR" the adoption of the Merger Agreement; and (2) "FOR" the adjournment of the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting.

Q:

What should I do if I receive more than one set of voting materials?

A:

Please sign, date and return (or grant your proxy electronically over the Internet or by telephone using the instructions provided in the enclosed proxy card) each proxy card and voting instruction card that you receive.

You may receive more than one set of voting materials, including multiple copies of this proxy statement and multiple proxy cards or voting instruction cards. For example, if you hold your shares in more than one brokerage account, you will receive a separate voting instruction card for each brokerage account in which you hold shares. If you are a stockholder of record and your shares are registered in more than one name, you will receive more than one proxy card.

Q:

Where can I find the voting results of the Special Meeting?

A:

If available, Marketo may announce preliminary voting results at the conclusion of the Special Meeting. Marketo intends to publish final voting results in a Current Report on Form 8-K to be filed with the SEC following the Special Meeting. All reports that Marketo files with the SEC are publicly available when filed. For more information, please see the section of this proxy statement captioned, "Where You Can Find More Information."

Q:

Will I be subject to U.S. federal income tax upon the exchange of common stock for cash pursuant to the Merger?

A:

If you are a U.S. Holder (as defined under the caption "The Merger—Material U.S. Federal Income Tax Consequences of the Merger"), the exchange of common stock for cash pursuant to the Merger will be a taxable transaction for U.S. federal income tax purposes, which generally will require a U.S. Holder to recognize gain or loss for U.S. federal income tax purposes in an amount equal to the difference, if any, between the amount of cash received by such U.S. Holder in the Merger with respect to such shares and such U.S. Holder's adjusted tax basis in the shares of common stock surrendered in the Merger. Backup withholding tax may also apply to the cash payments made pursuant to the Merger, unless the U.S. Holder complies with certification procedures under the backup withholding tax rules.

A Non-U.S. Holder (as defined under the caption "The Merger—Material U.S. Federal Income Tax Consequences of the Merger") generally will not be subject to U.S. federal income tax with respect to the exchange of common stock for cash in the Merger unless such Non-U.S. Holder has certain connections to the United States. A Non-U.S. Holder may, however, be subject to backup withholding tax with respect to the cash payments made pursuant to the Merger, unless the holder complies with certain certification procedures or otherwise establishes a valid exemption from backup withholding tax.

You should read "The Merger—Material U.S. Federal Income Tax Consequences of the Merger." Because particular circumstances may differ, we recommend that you also consult your own tax advisor to determine the U.S. federal income tax consequences relating to the Merger in light of

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your own particular circumstances and any consequences arising under the laws of any state, local or non-U.S. taxing jurisdiction.

Q:

What will the holders of Marketo Options and Stock-Based Awards receive in the Merger?

A:

At the Effective Time, and without any action required by any holder of an Option, each Option (or portion thereof) that is outstanding as of immediately prior to the Effective Time, whether vested or unvested:

(i)

with an exercise price per share less than $35.25, will be cancelled and converted into the right to receive an amount in cash equal to (a) the Per Share Merger Consideration (less the exercise price per share attributable to such Option), multiplied by (b) the total number of shares of common stock that are issuable upon the full exercise of such Option, minus (c) any applicable withholding taxes; and

(ii)

with an exercise price per share equal to or greater than $35.25, will be cancelled without payment of any consideration.

At the Effective Time, and without any action required by any holder of a Stock-Based Award, each Stock-Based Award that is outstanding as of immediately prior to the Effective Time, whether vested or unvested, will be cancelled and converted into the right to receive an amount equal to the (a) Per Share Merger Consideration (less the exercise price per share, if any, attributable to such stock-based award), multiplied by:

(i)

in the case of any Stock-Based Award that is only subject to time-vesting requirements, (b) the total number of shares of common stock that are subject to such Stock-Based Award, minus (c) any applicable withholding taxes; or



(ii)

in the case of any Stock-Based Award that is subject to time- and performance-vesting requirements, (b) the total number of shares of common stock determined pursuant to the "change in control" provisions of the award agreement underlying such Stock-Based Award (with the remaining time-vesting requirements deemed satisfied), minus (c) any applicable withholding taxes.

Q:

What will happen to the ESPP?

A:

The Merger Agreement provides that no new purchase periods will begin under the ESPP after May 27, 2016, and no individual will be allowed to begin participating in the ESPP after May 27, 2016. In addition, ESPP participants will not be permitted to increase the rate of payroll contributions to the ESPP from the rate in effect at the beginning of the current purchase period in progress or to make separate non-payroll contributions to the ESPP on or after May 27, 2016. All outstanding purchase rights under the ESPP will automatically be exercised no later than one business day before the Effective Time (with such purchase rights subject any pro rata adjustments that must be made if the current purchase period in progress must be shortened), and the ESPP will terminate as of the Effective Time. Each share of common stock purchased under the ESPP that remains outstanding as of immediately prior to the Effective Time will be cancelled at the Effective Time and converted into the right to receive the Per Share Merger Consideration.

Q:

When do you expect the Merger to be completed?

A:

We are working toward completing the Merger as quickly as possible and currently expect to complete the Merger in the third calendar quarter of 2016. However, the exact timing of completion of the Merger cannot be predicted because the Merger is subject to the closing conditions specified in the Merger Agreement, many of which are outside of our control, and the

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completion of the Marketing Period that Parent may use to complete its debt financing, if any, for the Merger.

Q:

Am I entitled to appraisal rights under the DGCL?

A:

If the Merger Agreement is adopted by stockholders, stockholders who do not vote in favor of the adoption of the Merger Agreement and who properly demand appraisal of their shares will be entitled to appraisal rights in connection with the Merger under Section 262 of the DGCL. This means that holders of shares of common stock are entitled to have their shares appraised by the Delaware Court of Chancery and to receive payment in cash of the "fair value" of the shares of common stock, exclusive of any elements of value arising from the accomplishment or expectation of the Merger, together with interest to be paid on the amount determined to be fair value, if any, as determined by the court. Stockholders who wish to seek appraisal of their shares are in any case encouraged to seek the advice of legal counsel with respect to the exercise of appraisal rights due to the complexity of the appraisal process. The DGCL requirements for exercising appraisal rights are described in additional detail in this proxy statement, and the relevant section of the DGCL regarding appraisal rights is reproduced in Annex C to this proxy statement.

Q:

Do any of Marketo's directors or officers have interests in the Merger that may differ from those of Marketo's stockholders generally?

A:

Yes. In considering the recommendation of the Board of Directors with respect to the proposal to adopt the Merger Agreement, you should be aware that our directors and executive officers may have interests in the Merger that are different from, or in addition to, the interests of stockholders generally. In: (1) evaluating and negotiating the Merger Agreement; (2) approving the Merger Agreement and the Merger; and (3) recommending that the Merger Agreement be adopted by stockholders, the Board of Directors was aware of and considered these interests, among other matters, to the extent that these interests existed at the time. For more information, please see the section of this proxy statement captioned, "The Merger—Interests of Marketo's Directors and Executive Officers in the Merger."

Q:

Who can help answer my questions?

A:

If you have any questions concerning the Merger, the Special Meeting or the accompanying proxy statement, would like additional copies of the accompanying proxy statement or need help voting your shares of common stock, please contact our proxy solicitor:

Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, NY 10022
Call toll-free: (888) 750-5834

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FORWARD-LOOKING STATEMENTS

        This proxy statement, the documents to which we refer you in this proxy statement and information included in oral statements or other written statements made or to be made by us or on our behalf contain "forward-looking statements" that do not directly or exclusively relate to historical facts. You can typically identify forward-looking statements by the use of forward-looking words, such as "may," "should," "could," "project," "believe," "anticipate," "expect," "estimate," "continue," "potential," "plan," "forecast" and other words of similar import. Stockholders are cautioned that any forward-looking statements are not guarantees of future performance and may involve significant risks and uncertainties, and that actual results may vary materially from those in the forward-looking statements. These risks and uncertainties include, but are not limited to, the risks detailed in our filings with the SEC, including in our most recent filings on Forms 10-K and 10-Q, factors and matters described or incorporated by reference in this proxy statement, and the following factors:

•

the inability to complete the Merger due to the failure to obtain stockholder approval or failure to satisfy the other conditions to the completion of the Merger, including, but not limited to, receipt of required regulatory approvals;



•

the risk that the Merger Agreement may be terminated in circumstances that require us to pay Parent a termination fee of $49.2 million;



•

the outcome of any legal proceedings that may be instituted against us and others related to the Merger Agreement;



•

risks that the proposed Merger disrupts our current operations or affects our ability to retain or recruit key employees;



•

the fact that receipt of the all-cash Merger consideration would be taxable to stockholders that are treated as U.S. Holders for U.S. federal income tax purposes;



•

the fact that, if the Merger is completed, stockholders will forgo the opportunity to realize the potential long-term value of the successful execution of Marketo's current strategy as an independent public company;



•

the possibility that Parent could, at a later date, engage in unspecified transactions, including restructuring efforts, special dividends or the sale of some or all of Marketo's assets to one or more as yet unknown purchasers, that could conceivably produce a higher aggregate value than that available to stockholders in the Merger;



•

the fact that under the terms of the Merger Agreement, Marketo is unable to solicit other Acquisition Proposals during the pendency of the Merger;



•

the effect of the announcement or pendency of the Merger on our business relationships, operating results and business generally;



•

the amount of the costs, fees, expenses and charges related to the Merger Agreement or the Merger;



•

risks related to the Merger diverting management's or employees' attention from ongoing business operations;



•

risks that our stock price may decline significantly if the Merger is not completed; and



•

risks related to obtaining the requisite consents to the Merger, including the timing and receipt of regulatory approvals from various domestic or foreign governmental entities, as the case may be, including any conditions, limitations or restrictions placed on these approvals, and the risk that one or more governmental entities (whether domestic or foreign) may deny approval.

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        Consequently, all of the forward-looking statements that we make in this proxy statement are qualified by the information contained or incorporated by reference herein, including: (1) the information contained under this caption; and (2) the information contained under the caption, "Risk Factors," and information in our consolidated financial statements and notes thereto included in our most recent filings on Forms 10-K and 10-Q. No assurance can be given that these are all of the factors that could cause actual results to vary materially from the forward-looking statements.

        Except as required by applicable law, we undertake no obligation to publicly update forward-looking statements, whether as a result of new information, future events or otherwise. Stockholders are advised to consult any future disclosures that we make on related subjects as may be detailed in our other filings made from time to time with the SEC.

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THE SPECIAL MEETING

        The enclosed proxy is solicited on behalf of the Board of Directors for use at the Special Meeting.

Date, Time and Place

        We will hold the Special Meeting on Thursday, July 28, 2016, at Marketo's headquarters, located at 901 Mariners Island Blvd., 1^st Floor, San Mateo, CA 94404, at 2:30 p.m. Pacific time.

Purpose of the Special Meeting

        At the Special Meeting, we will ask stockholders to vote on proposals to: (1) adopt the Merger Agreement; and (2) adjourn the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting.

Record Date; Shares Entitled to Vote; Quorum

        Only stockholders of record as of the Record Date are entitled to notice of the Special Meeting and to vote at the Special Meeting. A list of stockholders entitled to vote at the Special Meeting will be available at our principal executive offices located at 901 Mariners Island Blvd., Suite 500, San Mateo, CA 94404, during regular business hours for a period of no less than ten days before the Special Meeting and at the place of the Special Meeting during the meeting.

        As of the Record Date, there were 45,027,099 shares of common stock outstanding and entitled to vote at the Special Meeting.

        The holders of a majority of the stock issued and outstanding and entitled to vote thereat, present in person or represented by proxy, will constitute a quorum at the Special Meeting. In the event that a quorum is not present at the Special Meeting, it is expected that the meeting will be adjourned to solicit additional proxies.

Vote Required; Abstentions and Broker Non-Votes

        The affirmative vote of the holders of a majority of the outstanding shares of common stock is required to adopt the Merger Agreement. Adoption of the Merger Agreement by stockholders is a condition to the closing of the Merger.

        Approval of the proposal to adjourn the Special Meeting, whether or not a quorum is present, requires the affirmative vote of a majority of the voting power of the shares present in person or represented by proxy and entitled to vote at the Special Meeting.

        If a stockholder abstains from voting, that abstention will have the same effect as if the stockholder voted "AGAINST" the proposal to adopt the Merger Agreement. For stockholders who attend the meeting or are represented by proxy and abstain from voting, the abstention will have the same effect as if the stockholder voted "AGAINST" any proposal to adjourn the Special Meeting to a later date to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting.

        Each "broker non-vote" will also count as a vote "AGAINST" the proposal to adopt the Merger Agreement, but will have no effect on any proposal to adjourn the Special Meeting to a later date to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting. A "broker non-vote" generally occurs when a bank, broker or other nominee holding shares on your behalf does not vote on a proposal because the bank, broker or other nominee has not received your voting instructions and lacks discretionary power to vote the shares. "Broker non-votes," if any, will be counted for the purpose of determining whether a quorum is present.

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Shares Held by Marketo's Directors and Executive Officers

        As of the Record Date, our directors and executive officers beneficially owned and were entitled to vote, in the aggregate, 2,945,962 shares of common stock, representing approximately 6.5% of the shares of common stock outstanding on the Record Date.

        Our directors and executive officers have informed us that they currently intend to vote all of their respective shares of common stock (1) "FOR" the adoption of the Merger Agreement and (2) "FOR" the adjournment of the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting.

Voting of Proxies

        If your shares are registered in your name with our transfer agent, Computershare Trust Company, N.A, you may cause your shares to be voted by returning a signed and dated proxy card in the accompanying prepaid envelope, or you may vote in person at the Special Meeting. Additionally, you may grant a proxy electronically over the Internet or by telephone (using the instructions provided in the enclosed proxy card). You must have the enclosed proxy card available, and follow the instructions on the proxy card, in order to grant a proxy electronically over the Internet or by telephone. Based on your proxy cards or Internet and telephone proxies, the proxy holders will vote your shares according to your directions.

        If you plan to attend the Special Meeting and wish to vote in person, you will be given a ballot at the Special Meeting. If your shares are registered in your name, you are encouraged to vote by proxy even if you plan to attend the Special Meeting in person. If you attend the Special Meeting and vote in person by ballot, your vote will revoke any previously submitted proxy.

        Voting instructions are included on your proxy card. All shares represented by properly signed and dated proxies received in time for the Special Meeting will be voted at the Special Meeting in accordance with the instructions of the stockholder. Properly signed and dated proxies that do not contain voting instructions will be voted: (1) "FOR" adoption of the Merger Agreement; and (2) "FOR" the adjournment of the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting.

        If your shares are held in "street name" through a bank, broker or other nominee, you may vote through your bank, broker or other nominee by completing and returning the voting form provided by your bank, broker or other nominee or attending the Special Meeting and voting in person with a "legal proxy" from your bank, broker or other nominee. If such a service is provided, you may vote over the Internet or telephone through your bank, broker or other nominee by following the instructions on the voting form provided by your bank, broker or other nominee. If you do not return your bank's, broker's or other nominee's voting form, do not vote via the Internet or telephone through your bank, broker or other nominee, if possible, or do not attend the Special Meeting and vote in person with a "legal proxy" from your bank, broker or other nominee, it will have the same effect as if you voted "AGAINST" the proposal to adopt the Merger Agreement but will not have any effect on the adjournment proposal.

Revocability of Proxies

        If you are a stockholder of record, you may change your vote or revoke your proxy at any time before it is voted at the Special Meeting by:

•

signing another proxy card with a later date and returning it to us prior to the Special Meeting;

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•

submitting a new proxy electronically over the Internet or by telephone after the date of the earlier submitted proxy;



•

delivering a written notice of revocation to our Corporate Secretary; or



•

attending the Special Meeting and voting in person by ballot.

        If you have submitted a proxy, your appearance at the Special Meeting will not have the effect of revoking your prior proxy; provided that you do not vote in person or submit an additional proxy or revocation, which, in each case, will have the effect of revoking your proxy.

        If you hold your shares of common stock in "street name," you should contact your bank, broker or other nominee for instructions regarding how to change your vote. You may also vote in person at the Special Meeting if you obtain a "legal proxy" from your bank, broker or other nominee.

        Any adjournment, postponement or other delay of the Special Meeting, including for the purpose of soliciting additional proxies, will allow stockholders who have already sent in their proxies to revoke them at any time prior to their use at the Special Meeting as adjourned, postponed or delayed.

Board of Directors' Recommendation

        The Board of Directors, after considering various factors described under the caption, "The Merger—Recommendation of the Board of Directors and Reasons for the Merger," has unanimously: (1) determined that the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement are fair to, advisable and in the best interests of Marketo and its stockholders; and (2) adopted and approved the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement.

        Accordingly, the Board of Directors unanimously recommends that you vote: (1) "FOR" the adoption of the Merger Agreement; and (2) "FOR" the adjournment of the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting.

Solicitation of Proxies

        The expense of soliciting proxies will be borne by Marketo. We have retained Innisfree M&A Incorporated ("Innisfree"), a proxy solicitation firm, to solicit proxies in connection with the Special Meeting at a cost of approximately $25,000, plus expenses. We will also indemnify Innisfree against losses arising out of its provisions of these services on our behalf. In addition, we may reimburse banks, brokers and other nominees representing beneficial owners of shares for their expenses in forwarding soliciting materials to such beneficial owners. Proxies may also be solicited by our directors, officers and employees, personally or by telephone, email, fax, over the Internet or other means of communication. No additional compensation will be paid for such services.

Anticipated Date of Completion of the Merger

        Assuming timely satisfaction of necessary closing conditions, including the approval by stockholders of the proposal to adopt the Merger Agreement, and the completion of the Marketing Period that Parent may use to complete its debt financing, if any, for the Merger, we anticipate that the Merger will be consummated in the third calendar quarter of 2016.

Appraisal Rights

        If the Merger is consummated, stockholders who do not vote in favor of the adoption of the Merger Agreement and who properly demand appraisal of their shares will be entitled to appraisal rights in connection with the Merger under Section 262 of the DGCL. This means that holders of

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shares of common stock are entitled to have their shares appraised by the Delaware Court of Chancery and to receive payment in cash of the "fair value" of their shares of common stock, exclusive of any elements of value arising from the accomplishment or expectation of the Merger, together with interest to be paid on the amount determined to be fair value, if any, as determined by the court, so long as they comply with the procedures established by Section 262 of the DGCL. Due to the complexity of the appraisal process, stockholders who wish to seek appraisal of their shares are encouraged to seek the advice of legal counsel with respect to the exercise of appraisal rights.

        Stockholders considering seeking appraisal should be aware that the fair value of their shares as determined pursuant to Section 262 of the DGCL could be more than, the same as or less than the value of the consideration that they would receive pursuant to the Merger Agreement if they did not seek appraisal of their shares.

        To exercise your appraisal rights, you must: (1) submit a written demand for appraisal to Marketo before the vote is taken on the adoption of the Merger Agreement; (2) not submit a proxy or otherwise vote in favor of the proposal to adopt the Merger Agreement; and (3) continue to hold your shares of common stock of record through the Effective Time. Your failure to follow exactly the procedures specified under the DGCL will result in the loss of your appraisal rights. The DGCL requirements for exercising appraisal rights are described in further detail in this proxy statement, and the relevant section of the DGCL regarding appraisal rights is reproduced and attached as Annex C to this proxy statement. If you hold your shares of common stock through a bank, brokerage firm or other nominee and you wish to exercise appraisal rights, you should consult with your bank, brokerage firm or other nominee to determine the appropriate procedures for the making of a demand for appraisal by such bank, brokerage firm or nominee.

Other Matters

        At this time, we know of no other matters to be voted on at the Special Meeting. If any other matters properly come before the Special Meeting, your shares of common stock will be voted in accordance with the discretion of the appointed proxy holders.

Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to be Held on Thursday, July 28, 2016

        The proxy statement is available at http://investors.marketo.com.

Householding of Special Meeting Materials

        Unless we have received contrary instructions, we may send a single copy of this proxy statement to any household at which two or more stockholders reside if we believe the stockholders are members of the same family. Each stockholder in the household will continue to receive a separate proxy card. This process, known as "householding," reduces the volume of duplicate information received at your household and helps to reduce our expenses.

        If you would like to receive your own set of our disclosure documents this year or in future years, please contact us using the instructions set forth below. Similarly, if you share an address with another stockholder and together both of you would like to receive only a single set of our disclosure documents, please contact us using the instructions set forth below.

        If you are a stockholder of record, you may contact us by writing to Marketo's Investor Relations at 901 Mariners Island Blvd., Suite 500, San Mateo, CA 94404. Eligible stockholders of record receiving multiple copies of this proxy statement can request householding by contacting us in the same manner. If a bank, broker or other nominee holds your shares, please contact your bank, broker or other nominee directly.

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Questions and Additional Information

        If you have any questions concerning the Merger, the Special Meeting or the accompanying proxy statement, would like additional copies of the accompanying proxy statement or need help voting your shares of common stock, please contact our proxy solicitor:

Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, NY 10022
Call toll-free: (888) 750-5834

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THE MERGER

        This discussion of the Merger is qualified in its entirety by reference to the Merger Agreement, which is attached to this proxy statement as Annex A and incorporated into this proxy statement by reference. You should carefully read and consider the entire Merger Agreement, which is the legal document that governs the Merger, because this document contains important information about the Merger and how it affects you.

Parties Involved in the Merger

Marketo, Inc.
901 Mariners Island Blvd., Suite 500
San Mateo, CA 94404

        Marketo is the provider of a leading cloud-based Engagement Marketing Platform that is purpose-built to enable organizations ranging from small and medium businesses to the world's largest enterprises to engage in modern relationship marketing. Marketo's platform enables the effective execution, management and analytical measurement of online, social, mobile and offline marketing activities and customer interactions in today's data-centric, multi-channel business environment. Headquartered in San Mateo, CA, with offices around the world, Marketo serves as a strategic partner to large enterprise and fast-growing small companies across a wide variety of industries.

        Marketo's common stock is listed on the NASDAQ, under the symbol "MKTO."

Milestone Holdco, LLC
c/o Vista Equity Partners Management, LLC
Four Embarcadero Center, 20th Floor
San Francisco, CA 94111

        Parent was formed on May 25, 2016, solely for the purpose of engaging in the transactions contemplated by the Merger Agreement, and has not engaged in any business activities other than in connection with the transactions contemplated by the Merger Agreement and arranging of the equity financing and any debt financing in connection with the Merger.

Milestone Merger Sub, Inc.
c/o Vista Equity Partners Management, LLC
Four Embarcadero Center, 20th Floor
San Francisco, CA 94111

        Merger Sub is a wholly owned direct subsidiary of Parent and was formed on May 25, 2016, solely for the purpose of engaging in the transactions contemplated by the Merger Agreement, and has not engaged in any business activities other than in connection with the transactions contemplated by the Merger Agreement and arranging of the equity financing and any debt financing in connection with the Merger.

        Parent and Merger Sub are each affiliated with Vista Equity Partners Fund VI, L.P., and Parent, Merger Sub and Vista Fund VI are each affiliated with Vista. Vista is a leading private equity firm focused on investments in software, data and technology-enabled companies. At the Effective Time, Marketo, as the Surviving Corporation, will be indirectly owned by Vista Fund VI.

        In connection with the transactions contemplated by the Merger Agreement, Vista Fund VI has provided Parent with an equity commitment of up to approximately $1.79 billion in cash, which will be available to fund the aggregate purchase price and the other payments contemplated by, and subject to the terms and conditions of, the Merger Agreement. For more information, please see the section of this proxy statement captioned, "The Merger—Financing of the Merger."

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Effect of the Merger

        Upon the terms and subject to the conditions of the Merger Agreement, Merger Sub will merge with and into Marketo, with Marketo continuing as the Surviving Corporation. As a result of the Merger, Marketo will become a wholly owned direct subsidiary of Parent, and our common stock will no longer be publicly traded and will be delisted from the NASDAQ. In addition, our common stock will be deregistered under the Exchange Act, and we will no longer file periodic reports with the SEC. If the Merger is completed, you will not own any shares of the capital stock of the Surviving Corporation.

        The Effective Time will occur upon the filing of a certificate of merger with the Secretary of State of the State of Delaware (or at such later time as we, Parent and Merger Sub may agree and specify in the certificate of merger).

Effect on Marketo if the Merger is Not Completed

        If the Merger Agreement is not adopted by stockholders, or if the Merger is not completed for any other reason:

(i)

the stockholders will not be entitled to, nor will they receive, any payment for their respective shares of common stock pursuant to the Merger Agreement;



(ii)

(A) Marketo will remain an independent public company, (B) Marketo's common stock will continue to be listed and traded on the NASDAQ and registered under the Exchange Act, and (C) Marketo will continue to file periodic reports with the SEC;



(iii)

we anticipate that (A) management will operate the business in a manner similar to that in which it is being operated today and (B) stockholders will be subject to similar types of risks and uncertainties as those to which they are currently subject, including, but not limited to, risks and uncertainties with respect Marketo's business, prospects or results of operations, as such may be affected by, among other things, the highly competitive industry in which Marketo operates and adverse economic conditions;



(iv)

the price of our common stock may decline significantly, and if that were to occur, it is uncertain when, if ever, the price of our common stock would return to the price at which it trades as of the date of this proxy statement;



(v)

the Board of Directors will continue to evaluate and review Marketo's business operations, strategic direction and capitalization, among other things, and will make such changes as are deemed appropriate (irrespective of these efforts, it is possible that no other transaction acceptable to the Board of Directors will be offered or that Marketo's business, prospects or results of operations will be adversely impacted); and,



(vi)

under certain specified conditions, Marketo will be required to pay Parent a termination fee of $49.2 million upon the termination of the Merger Agreement. For more information, please see the section of this proxy statement captioned, "Proposal 1: Adoption of the Merger Agreement—Termination Fee."

Merger Consideration

        At the Effective Time, and without any action required by any stockholder, each share of common stock (other than Excluded Shares, which include, for example, shares of common stock owned by stockholders who have properly and validly exercised their statutory rights of appraisal in accordance with Section 262 of the DGCL) outstanding as of immediately prior to the Effective Time will be cancelled and extinguished, and automatically converted into the right to receive the Per Share Merger Consideration, without interest thereon and less any applicable withholding taxes.

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        After the Merger is completed, you will have the right to receive the Per Share Merger Consideration in respect of each share of common stock that you own (less any applicable withholding taxes), but you will no longer have any rights as a stockholder (except that stockholders who properly exercise their appraisal rights will have a right to receive payment of the "fair value" of their shares as determined pursuant to an appraisal proceeding, as contemplated by Delaware law). For more information, please see the section of this proxy statement captioned, "The Merger—Appraisal Rights."

Background of the Merger

        The Board of Directors regularly evaluates Marketo's strategic direction, ongoing business plans and prospects with a view toward enhancing stockholder value. As part of this evaluation, the Board of Directors has from time to time considered a variety of strategic alternatives for Marketo, including (i) the continuation of Marketo's business plan as an independent enterprise; (ii) modifications to Marketo's strategy and product direction; (iii) potential expansion opportunities into new business lines through acquisitions and combinations of Marketo with other businesses; and (iv) a possible sale of Marketo.

        During March and April 2016, Phillip Fernandez, the Chief Executive Officer and Chairman of Marketo, and Brian Kinion, the Chief Financial Officer of Marketo, met with representatives of Morgan Stanley to discuss generally Marketo's business and future opportunities for strategic growth and partnership building with other participants in its industry, as well as certain transactions in the SaaS space which had relevant implications for Marketo. During these conversations, representatives of Morgan Stanley discussed the possibility of introducing Marketo to third parties who might have interest in exploring commercial partnerships or other strategic relationships with Marketo and Mr. Fernandez generally supported this in concept.

        Morgan Stanley arranged several of these meetings in April 2016. On April 13, 2016, a representative of Morgan Stanley introduced Mr. Fernandez to a representative of a strategic party, which we refer to as "Party A". During their meeting, Party A and Marketo discussed the existing commercial relationship between Party A and Marketo and opportunities to strengthen that relationship through additional collaboration. On April 18, 2016, a representative of Morgan Stanley had a telephone conversation with a representative of a second strategic party, which we refer to as "Party B". During the discussion, the representative of Morgan Stanley and the representative of Party B discussed, among other things, the existing commercial relationship between Party B and Marketo and other potential opportunities for the parties to work together. On April 21, 2016, a representative of Morgan Stanley communicated with a representative of a third strategic party, which we refer to as "Party C", to inquire about Party C's interest in establishing a business partnership with Marketo to integrate certain of their respective products more closely. The representative of Party C requested a follow-up meeting or a telephone conversation with Marketo to further evaluate the possibility and merits of doing so. During each of the meetings with Party A, Party B and Party C, no proposals were made by any party nor were there any discussions regarding a potential acquisition of Marketo.

        In addition to these meetings arranged by Morgan Stanley, from time to time Mr. Fernandez also had meetings and conversations with representatives of various private equity funds with investments in SaaS companies and general interest and expertise in the SaaS industry. Along these lines and at the request of Vista, on April 27, 2016, Mr. Fernandez met with representatives of Vista to discuss standardizing Vista's portfolio companies on the Marketo platform. During the course of this meeting, the representatives of Vista expressed Vista's interest in acquiring Marketo and suggested that the premium in such an acquisition may be comparable to that of Vista's recent acquisitions, including its recently announced agreement to acquire Cvent, Inc., but Vista made no specific proposal at such time.

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        On April 27, 2016, Mr. Fernandez, Mr. Kinion, and Fred Ball, the Executive Vice President and Chief Administrative Officer of Marketo, had a meeting with representatives of a financial sponsor, which we refer to as "Party D", to discuss developments in the SaaS industry. During these discussions, Mr. Fernandez and the representatives of Party D discussed Marketo's business, its industry and the opportunities for collaboration between the parties. Party D expressed an interest in continuing to discuss with Marketo opportunities on which the parties could work together more seriously but did not indicate an interest in acquiring Marketo at such time.

        On April 28, 2016, Mr. Fernandez communicated by email to the Board of Directors to inform them of his discussion with representatives of Vista regarding Vista's interest in acquiring Marketo. A special meeting of the Board of Directors was scheduled to discuss Vista's expression of interest.

        On May 1, 2016, the Board of Directors held a special meeting with members of Marketo management and a representative of Wilson Sonsini Goodrich & Rosati P.C. ("Wilson Sonsini"), outside legal counsel to Marketo. Mr. Fernandez apprised the Board of his recent meeting with Vista in which Vista had expressed potential interest in acquiring Marketo and had suggested that the premium in such an acquisition may be comparable to that of Vista's recent acquisitions, including its recently announced agreement to acquire Cvent, Inc., which the Board of the Directors interpreted to suggest that Vista was signaling a price per share in the "mid-$30s" for a potential acquisition of Marketo. Mr. Fernandez also apprised the Board of his other meetings throughout April and the feedback he had received from the parties with whom had had met. Messrs. Fernandez and Ball then provided the Board of Directors with a general update on Marketo's business performance and outlook for the near term, including Marketo's recent financial results, Marketo's current financial guidance to investors and "sell-side" analysts, the general financial outlook for the quarter and the full year, and the status of new product development, as well as the status of key customers and the status of Marketo's sales transition. A representative from Wilson Sonsini then discussed with the Board of Directors their fiduciary duties in the context of strategic transactions, including at the preliminary stages of evaluating an acquisition proposal. The Board of Directors also discussed the potential engagement of investment banks to, among other things, assist Marketo in assessing its long-term stand-alone value, evaluating offers for a strategic transaction, evaluating the merits of engaging in discussions with others potentially interested in a strategic transaction, and providing other customary assistance in connection with a potential transaction. The Board of Directors discussed the potential benefits of forming a transaction committee of the Board of Directors to manage the strategic review process and potential sale of Marketo. After these discussions, management left the meeting and the Board of Directors met in an executive session with a representative of Wilson Sonsini. While in executive session, the Board of Directors discussed the engagement of a qualified financial advisor to assist Marketo and the Board of Directors with its evaluation of any indications of interest received by Marketo and the related strategic review process. Following the discussion, the Board of Directors authorized Marketo's management to begin discussions with Morgan Stanley to serve in this capacity and to direct Morgan Stanley to contact Vista to discuss the seriousness of its expression of interest in a potential acquisition of Marketo. Morgan Stanley was selected based on Morgan Stanley's qualifications, expertise and reputation, its knowledge of and involvement in recent transactions in the SaaS industry, and its knowledge and understanding of Marketo's business and affairs. The Board of Directors then engaged in a further discussion of the merits of forming a transaction committee in connection with the Board's evaluation of transaction proposals and the related strategic process, and determined to form the Transaction Committee of the Board of Directors (the "Transaction Committee") to supervise the overall process and ensure active board involvement in strategic decisions throughout. Independent directors Roger Siboni, Tae Hea Nahm and Cammie Dunaway were selected to serve on the Transaction Committee. Mr. Siboni was selected to serve as Chairman of the Transaction Committee.

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        On May 2, 2016, members of Marketo's management had a telephone call with representatives of Morgan Stanley to discuss Vista's expression of interest and the related strategic process. During this call, Marketo management directed Morgan Stanley to contact Vista to determine the seriousness of its expression of interest in a potential acquisition of Marketo.

        On May 3, 2016, a representative of Morgan Stanley had a telephone conversation with representatives of Vista to gauge the strength of Vista's interest in an acquisition of Marketo. Vista provided an initial verbal indication of interest of "low-$30s" per share. Morgan Stanley advised Vista that the Board of Directors was not likely to have interest in a sale at that price and advised that Vista's proposal would likely need to be in the "mid-$30s" per share in cash in order to interest the Board of Directors in further discussions, given the Board of Directors prior interpretation of Vista's suggestion that a potential transaction may be at a premium comparable to that of Vista's recent transactions.

        On May 6, 2016, a representative of Morgan Stanley had a meeting with a representative of a strategic party, which we refer to as "Party E", which had previously been scheduled by Morgan Stanley and Party E prior to the Board of Directors' evaluation of a potential strategic transaction. Following a general discussion on several topics unrelated to Marketo, Morgan Stanley, on the prior advice of Marketo's management, raised Marketo with Party E and inquired into Party E's interest in an acquisition of Marketo. The representative of Party E indicated that it was familiar with Marketo and its business, but that an acquisition of Marketo was not a strategic priority for Party E at the time.

        On May 8, 2016, the Board of Directors held a special meeting with members of Marketo's management and representatives of Morgan Stanley and Wilson Sonsini. At the meeting, Mr. Fernandez and Morgan Stanley provided an update regarding their recent discussions with Vista, Party A, Party B, Party C, Party D and Party E. Morgan Stanley also presented a list of additional parties that it believed might have strategic interest in a potential acquisition of Marketo. The Board of Directors discussed each of the listed parties and the likely interest of each in Marketo. Representatives of Morgan Stanley then left the meeting, and the Board of Directors met in executive session with members of management and Wilson Sonsini to discuss the proposed engagement of Morgan Stanley as Marketo's financial advisor. As part of this discussion, management outlined the material terms of the proposed engagement of Morgan Stanley, and Wilson Sonsini reviewed disclosure related to relationships between Vista and Morgan Stanley provided by Morgan Stanley prior to the meeting and noted that Morgan Stanley carried out its customary conflicts-related clearance procedures. Following this report, the Board of Directors authorized management to engage Morgan Stanley as Marketo's financial advisor on the terms presented. Members of Marketo's management then reviewed the two sets of long-term financial projections that management had prepared in the ordinary course and that would be provided to Morgan Stanley to conduct its financial analysis, the Higher Growth Case and the Leveraged Growth Case (Base Case), respectively (as more fully described below under the caption "The Merger—Marketo's Financial Projections"). The Board of Directors approved each of the Higher Growth Case and the Leveraged Growth Case for use by Morgan Stanley to conduct its financial analysis but directed Marketo's management and Morgan Stanley to provide only the Leveraged Growth Case to parties for the purposes of due diligence because the Board of Directors believed that the Leveraged Growth Case was more representative of Marketo's recent performance, growth and focus. All members of management then left the meeting, and the Board of Directors held an executive session with the representative of Wilson Sonsini. In this session, the Board of Directors discussed various strategies for maximizing stockholder value in a strategic process, including the scope of any market check, and determined to revisit the scope of the market check as the process evolved. During this executive session, the Board of Directors also discussed the importance of maintaining the objectiveness of management throughout the strategic process and agreed to instruct management to refrain from engaging in any discussions regarding their continuing employment or re-investment in Marketo without Board approval prior to the signing of any potential transaction.

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        Later in the day on May 8, 2016, Mr. Fernandez met with a representative of Party A to discuss the existing commercial relationship between Marketo and Party A, opportunities to strengthen that relationship, and, more generally, the strategic landscape and positioning in the marketing software space. Party A did not make any proposals regarding a potential transaction during this meeting.

        On May 10, 2016, news outlets reported that Marketo was working with Morgan Stanley on a strategic review process. Subsequent to this rumor, a number of parties contacted each of Marketo and Morgan Stanley.

        On May 10, 2016, a representative of Morgan Stanley had an initial telephone discussion with a representative of a financial sponsor, which we refer to as "Party F". During the discussions, Party F expressed strong interest in exploring a potential acquisition of Marketo and requested a meeting with Marketo's management team. Marketo granted its request, negotiated a non-disclosure agreement with Party F, and scheduled a management meeting, which was held on May 15, 2016.

        On May 12, 2016, a representative of Party A contacted Morgan Stanley to convey that it had seen the press rumors and that it was not likely that Marketo would be a strategic priority for Party A at the time.

        On May 12, 2016, a representative of Vista called Morgan Stanley and verbally communicated a revised proposal to acquire Marketo at a price of $34.00 - $35.00 per share in cash, and indicated that it hoped to arrive at a final proposal at the high end of that range following its due diligence review. Vista further noted that it did not anticipate requiring an extensive due diligence process. Vista sent a written indication of interest the following day reflecting the proposal along with a request that Marketo enter into exclusive negotiations with Vista. In its written indication of interest, Vista indicated that its proposal was contingent on completion of confirmatory due diligence (which it expected to be complete in 10 to 17 days) and was not contingent on arranging third party debt financing, which indicated that Vista was prepared to move quickly to reach a definitive agreement. Following receipt of Vista's proposal, Marketo negotiated a non-disclosure agreement with Vista and scheduled a management presentation with Vista's team, which was held on May 16, 2016.

        On May 13, 2016, Mr. Fernandez and representatives of Party D held a follow-up meeting during which they discussed a potential acquisition of Marketo by Party D. Party D requested a meeting with Marketo's broader management team. Marketo subsequently negotiated a non-disclosure agreement with Party D, and on May 13, 2016, Party D communicated to Morgan Stanley that Party D had an initial view on Marketo's valuation in the "high-$20s" per share. Morgan Stanley advised Party D that the Board of Directors would likely consider any proposal at that price to be insufficient and suggested that Party D would need to make a proposal in the "mid-$30s" per share in order to interest the Board of Directors in further discussions and be competitive with other interested parties.

        On May 14, 2016, the Transaction Committee held a special meeting with members of Marketo's management and representatives of Morgan Stanley and Wilson Sonsini. At the meeting, the Transaction Committee discussed, among other things, Vista's indication of interest and the status of discussion with all the parties that management and Morgan Stanley had contacted as part of the company's ongoing strategic process. Morgan Stanley gave its preliminary financial view on Vista's revised proposal to acquire Marketo for a price of $34.00 - $35.00 per share and potential responses to Vista's proposal. Morgan Stanley presented its preliminary financial analysis of Marketo and indicated that its analysis was ongoing. Morgan Stanley discussed with the Board of Directors the two sets of financial projections that management had prepared and provided to Morgan Stanley to conduct its financial analysis, the Higher Growth Case and the Leveraged Growth Case (Base Case), respectively. The Transaction Committee instructed Morgan Stanley to conduct its financial analysis on the basis of both sets of projections. The representatives of Wilson Sonsini then discussed with the Transaction Committee its fiduciary duties in the context of an acquisition transaction, including the various methods by which the Board of Directors can fulfil its duty to maximize stockholder value, as well as

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the fact that the news media speculations regarding a sales process was likely serving as a passive market check for Marketo and could supplement the existing process. The Transaction Committee then engaged in a discussion regarding Vista's request for exclusivity and concluded that entering into exclusivity with any party would be premature at this time. The Transaction Committee discussed various strategies and methods by which the Board of Directors might seek to maximize stockholder value. Among the topics discussed by the Transaction Committee were: (i) the parameters of engagement with Vista and Vista's desire to move quickly to a negotiated agreement; (ii) the ability of other parties to conduct due diligence on a competitive timeline; (iii) ability to maintain competitive tension between Vista and the other parties; (iv) recent transaction history of Vista; and (v) the likely level of interest by both parties already part of the solicitation process and other potential parties that had not yet been contacted. Following this discussion, the Transaction Committee then held an executive session without Morgan Stanley where the committee further discussed the parameters of the market check process. The Transaction Committee then held a second executive session without members of management during which the committee discussed the potential for management conflicts of interest due to the presence of private equity sponsors and determined that, though they were unaware of any actual conflicts at such time, the Transaction Committee members would assume an active role in overseeing the market check process on behalf of the Board of Directors.

        On May 15, 2016, the Board of Directors held a special meeting with members of Marketo management and representatives of Morgan Stanley and Wilson Sonsini. Wilson Sonsini addressed the Board of Directors' fiduciary duties in connection with a possible sale of Marketo and reviewed relevant legal issues implicated by a potential sale of Marketo. Morgan Stanley provided an update on the status of discussions with all parties contacted during the market check process. The Board of Directors then discussed again with Morgan Stanley other third parties that could reasonably be expected to have strategic interest in acquiring Marketo and the financial capability to do so, as well as the potential strategies for engaging those parties in a discussion regarding a potential acquisition of Marketo. The Board of Directors also discussed with Morgan Stanley the risks and challenges that a broad market check could present, including the potential for additional leaks regarding a transaction and the downside of outreach to certain parties that are competitors that may seek access to Marketo's information for competitive purposes or that may leverage the uncertainty of a potential transaction in competing against Marketo in commercial opportunities. Representatives of Morgan Stanley and Wilson Sonsini also discussed the fact that, if the termination fees in a negotiated merger agreement were sufficiently low, other bidders would have the opportunity and ability to offer to acquire Marketo, subject to the payment of such termination fee, at a higher price even after Marketo signed a definitive agreement with another buyer. Representatives of Morgan Stanley and Wilson Sonsini further noted that, in light of the press rumors, strategically interested parties who were not contacted would likely contact Marketo or Morgan Stanley if they did have interest in acquiring Marketo. The Board of Directors discussed the benefits, on balance, of engaging with Vista on its requested accelerated timeline versus giving other interested parties sufficient time to consider making an acquisition proposal. After discussion, the Board of Directors directed Morgan Stanley to re-engage with Party A, Party B, Party C and Party E with an indication that time was of the essence and suggesting that they put forth an attractive proposal if they remained interested in a transaction with Marketo and wished to remain competitive in the solicitation process. The Board of Directors further directed Morgan Stanley to continue to engage Vista, Party D and Party F in discussions in an attempt to obtain a higher offer price from each of them. The Board of Directors then moved to an executive session without representatives of Morgan Stanley, where the Board of Directors further discussed whether or not to run a broad based solicitation process and which other potential bidders may have an interest in acquiring Marketo. The Board of Directors discussed the desirability of reaching out to a certain strategic party, which we refer to as "Party G", to gauge interest in a potential transaction with Marketo and requested that Marketo's management direct Morgan Stanley to contact Party G. Marketo's management also provided the Board of Directors with a general update on Marketo's

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business, including discussing the general outlook for the quarter and the year, and product, customer and partner matters. All members of management then left the meeting, and the Board of Directors met in an executive session with the representatives of Wilson Sonsini. During this portion of the meeting, the Board of Directors further discussed other third parties that may potentially be interested in acquiring Marketo and the general approach being taken in the market check process.

        Following the Board of Directors meeting, on May 15, 2016, Marketo and Morgan Stanley formally finalized the engagement with Morgan Stanley by executing an engagement letter.

        On May 16, 2016, a representative of Morgan Stanley communicated with a representative of a Party G to inquire if Party G was interested in a potential acquisition with Marketo. Party G indicated they were not interested in pursuing an acquisition at such time.

        On May 17, 2016, a representative of Morgan Stanley had a telephone conversation with a representative of Party C regarding Marketo. Party C did not provide an indication as to their level of interest at that time.

        On May 17, 2016, in response to earlier discussions, Party B communicated to Morgan Stanley that it had interest in exploring a potential transaction with Marketo and requested a meeting with management to discuss a potential transaction between the two companies. Marketo negotiated a non-disclosure agreement with Party B and scheduled a management presentation with it, which was held on May 20, 2016.

        On May 18, 2016, representatives of Marketo and representatives of Party F had a follow-up telephone call to further discuss Party F's financial due diligence questions regarding a potential transaction. Party F noted to Morgan Stanley that it was interested in further considering the opportunity, though it was not clear they would be competitive on price.

        On May 18, 2016, Marketo management and representatives of Morgan Stanley met with representatives of Party D to provide further due diligence and further discuss Marketo's business, operations and strategy. Party D indicated that they had a high level of interest in acquiring Marketo for cash and were trying to support internally getting to the "mid-$30s".

        On May 20, 2016, the Transaction Committee held a special meeting with members of Marketo's management and representatives of Morgan Stanley and Wilson Sonsini. At the meeting, Marketo's management provided the Transaction Committee with a general update on the indications of interest that Marketo had received and the management meetings that Marketo's management had held with each of Vista, Party D and Party F. A representative of Wilson Sonsini then updated the Transaction Committee on the status of negotiations of a confidentiality agreement with Party B, including that Party B refused to agree to a standstill provision in its confidentiality agreement with Marketo. The Transaction Committee discussed the merits of permitting Party B to participate in the process despite not having a standstill provision, including Party B's historical lack of hostile behavior in other transactions and the desirability of Party B's participation. The Transaction Committee then directed Marketo's management and Wilson Sonsini to accept the terms in the confidentiality agreement as proposed by Party B.

        On May 20, 2016, a representative of a strategic party, which we refer to as "Party H", made an unsolicited inquiry to a representative of Morgan Stanley, requesting participation in Marketo's strategic process based on press reports that Marketo was conducting one. Neither Marketo nor representatives of Morgan Stanley had previously contacted Party H to gauge Party H's interest in exploring a potential acquisition of Marketo because Party H was a competitor of Marketo and because Marketo believed that if Party H had interest in a potential acquisition of Marketo, Party H would make an in-bound inquiry following press reports speculating about Marketo's strategic process. Upon receipt of Party H's request to participate in the process, Marketo promptly granted its request,

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negotiated a non-disclosure agreement and scheduled a management presentation, which was held on May 23, 2016.

        On May 20, 2016, a representative of Party A communicated to a representative of Morgan Stanley that Party A had completed its internal assessment of a potential acquisition of Marketo, and that Party A would not be pursuing an acquisition of Marketo at such time.

        On May 21, 2016, the Transaction Committee held a special meeting with members of Marketo's management and representatives of Morgan Stanley and Wilson Sonsini. At the meeting, Marketo's management provided the Transaction Committee with a general update on Marketo's business and product, customer and partner matters. At the meeting, Morgan Stanley updated the Transaction Committee regarding the acquisition proposals that Marketo had received and on the status of discussions with the other potential bidders. Morgan Stanley advised that (i) it may be possible, as part of the negotiation process, to get Vista to increase its offer price above its previously proposed range of $34.00-$35.00 per share, but that any such increase would likely be only incrementally higher based on statements Vista had made in recent discussions; (ii) that Party D was contemplating, based on its due diligence, increasing its proposed offer price above the previously offered valuation of the "high-$20s" per share; and (iii) that it was sensing weakness from Party F regarding the price it was prepared to offer for Marketo. The Transaction Committee considered requests by each of Vista and Party D for Marketo to approve certain financing sources to receive confidential information under the non-disclosure between Marketo and Vista and Party D, respectively. The Transaction Committee approved each request, after considering the risks associated with such approval, including further leaks regarding the potential for a transaction involving Marketo. The representatives of Morgan Stanley provided the Transaction Committee with an update to its preliminary financial analysis of a potential transaction. Following this update and discussion, representatives of Morgan Stanley left the meeting, and the Transaction Committee met in an executive session with members of management and the representatives of Wilson Sonsini. Members of management provided the Transaction Committee with an update on the status of management meetings and follow-up diligence with the Vista, Party D, and the other potential bidders. Subsequently, all members of management left the meeting, and the Transaction Committee met in executive session with the members of Wilson Sonsini.

        On May 23, 2016, Party F called Morgan Stanley to inform Morgan Stanley that, as a result of Party F's due diligence, Party F was arriving at a valuation of Marketo that implied a purchase price in the "low-$30s" per share. Morgan Stanley advised Party F that in order to be of interest to the Board of Directors, Party F would need to propose a price in the "mid-$30s" per share in cash. The representative of Party F indicated that they were unlikely to make a proposal at that price level. Later that day, the representative of Party F communicated to Morgan Stanley that Party F was not likely to pursue an acquisition of Marketo at such time given the valuation expectations.

        On May 23, 2016, Marketo received a written indication of interest from Party D to acquire Marketo for $34.00 per share in cash. In its indication of interest, Party D indicated that it had committed to provide equity financing for the aggregate purchase price. Party's D proposal requested that Marketo engage with Party D on an exclusive basis and was contingent on the completion of both business and legal due diligence. Party D indicated that it expected to complete due diligence within one week. Party D's proposal was accompanied by a draft of a merger agreement and drafts of an equity commitment letter and other ancillary documents.

        On May 23, 2016, Mr. Fernandez had a telephone conversation with a representative of Party C to discuss Marketo's business, operations and strategy and potential synergy opportunities if the two companies combined. Party C specifically asked Mr. Fernandez what an expected purchase price for Marketo might be, to which Mr. Fernandez recommended that Party C discuss that topic with Morgan Stanley. Following the call, Morgan Stanley attempted on multiple occasions to contact Party C to gauge Party C's continued interest in a potential transaction with Marketo, but Morgan Stanley did not

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receive response from Party C. Morgan Stanley advised it believed that that the lack of a response from Party C was an indication that Party C was not interested in pursuing a transaction with Marketo at such time.

        On May 24, 2016, Vista submitted a revised proposal to acquire Marketo for $34.50 per share in cash, and also delivered a draft of a merger agreement, together with drafts of ancillary transaction documents, including an equity commitment letter and a limited guaranty. Vista's proposal indicated, subject to agreeing on the definitive documents, that (i) Vista would provide an equity commitment for the entire purchase price, (ii) Vista's potential liability would be limited to 6.5% of the equity value of Marketo, or approximately $116.3 million and (iii) Vista was prepared to pursue a transaction expeditiously. Vista further noted that its offer would expire at 5:00 p.m. Pacific time on May 25, 2016 if Marketo did not sign an exclusivity agreement with Vista.

        On May 24, 2016, Morgan Stanley had a follow-up telephone conversation with Party E to discuss Party E's interest in potentially acquiring Marketo. Party E indicated that it was completing its internal review on the potential for a transaction. Morgan Stanley communicated to Party E that Party E would need to make a decision quickly regarding whether to submit an offer to acquire Marketo.

        On the morning of May 25, 2016, the Transaction Committee held a special meeting with members of Marketo management and representatives of Morgan Stanley and Wilson Sonsini in attendance. At the meeting, representatives of Morgan Stanley updated the Transaction Committee on the proposed indications of interest that Marketo had received and advised the Transaction Committee that (i) they believed both Vista and Party D may have room to increase their offers above $34.50 and $34.00, respectively, but in each case likely not enough room to get a purchase price in the "high-$30s" per share; (ii) Vista would be prepared to enter into a definitive agreement as early as May 27, 2016, and (iii) Party D was modestly behind on due diligence and would require an additional week of due diligence before it was ready to enter a definitive agreement. Morgan Stanley also updated the Transaction Committee on the status of discussions with Party H. Morgan Stanley updated the Transaction Committee on the proposed indication of interest received from Party F, noting that Party F's valuation in the "low-$30s" per share was not competitive with the offers received from Vista and Party D. The Transaction Committee discussed the merits of entering into exclusive negotiations with either Vista or Party D. Morgan Stanley indicated that it believed that the request for exclusivity from whichever party ultimately prevailed with the highest bid was an important requirement of such party's proposal. The Transaction Committee discussed the possibility of entering into exclusivity with either party on a modified basis, such that the exclusivity would only apply with respect to Vista and Party D as against the other party, and would permit the other participants in the process more time to complete their evaluation. The Transaction Committee requested further information on the differences in contract terms between the offers from Vista and Party D. The Transaction Committee discussed the nature of performing a further market check and the importance of ensuring the winning bid included a termination fee sufficiently low to not preclude third-parties from offering a higher price after an initial deal is announced. Representatives of Morgan Stanley then left the meeting, and the Transaction Committee met in executive session with members of management and Wilson Sonsini. The Transaction Committee continued to discuss the status of the solicitation process. Following this discussion, all members of management left the meeting, and the Transaction Committee met in an executive session with the representatives of Wilson Sonsini.

        On May 25, 2016, Vista held a series of follow-up calls with Marketo management to complete confirmatory due diligence.

        On May 25, 2016, the Board of Directors held a special meeting with members of Marketo management and representatives of Morgan Stanley and Wilson Sonsini in attendance. At the meeting, a representative of Morgan Stanley updated the Board of Directors on (i) the proposed indications of interest that Marketo had received from Vista and Party D and (ii) the status of discussions with Party

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H. Morgan Stanley gave the Board of Directors an overview Party D's indication of interest, including Party's D revised bid of $34.00 per share, and an update on Party D's due diligence, noting that Party D was further behind Vista on due diligence but was holding management meetings later in the day to discuss remaining due diligence. Morgan Stanley then reviewed Vista's revised offer of $34.50 in cash and its request to enter into exclusivity. The Board of Directors discussed the status of Marketo's market check with potential strategic parties and the benefits, on balance, of continuing to reach out to other third parties that potentially may be interested in acquiring Marketo. The representatives of Morgan Stanley and Wilson Sonsini reviewed with the Board of Directors the relative strengths of each of Vista and Party D's proposed indications of interest, as well as the strategy of using a proposal for limited exclusivity to obtain higher offers from Vista and Party D. Morgan Stanley then reviewed its preliminary financial analysis of Marketo and the proposed indications of interest. Representatives of Morgan Stanley then left the meeting, and the Board of Directors met in executive session with members of management and Wilson Sonsini. The Board of Directors further discussed the status of discussions Party H and any other potential strategic buyers. Following this discussion, all members of management left the meeting, and the Board of Directors met in an executive session with the representatives of Wilson Sonsini. The Board of Directors further discussed the proposed offers received from Vista and Party D. The Board of Directors authorized Morgan Stanley to contact Vista and Party D immediately to request that both Vista and Party D submit their respective final offers and to contact Party H to inform them that timing is of the essence and that Party H should indicate its interest in the near future as other parties were exerting significant timing pressure on Marketo, including requests for exclusivity.

        On May 25, 2016, Marketo management and representatives of Morgan Stanley met with representatives of Party D to discuss Party D's bid and to help Party D solidify its view on valuation.

        Later in the day on May 25, 2016, a representative of Morgan Stanley asked each of Vista and Party D to submit its "best and final offer" by end of the day and the party that submitted the higher bid would get limited exclusivity relative to the other bidder. The Morgan Stanley representative encouraged each of Vista and Party D to increase their respective bids to $36.00 per share.

        On May 25, 2016, a representative of Party B communicated to a representative of Morgan Stanley that although it continued to have interest in the sector, it did not plan to pursue an acquisition of Marketo at such time.

        On May 25, 2016, a representative of Party H communicated to a representative of Morgan Stanley that it remained interested in a potential acquisition of Marketo and that it continued to discuss internally how the Marketo business would fit with Party H's existing business.

        Later in the day on May 25, 2016, Marketo received final bids from Vista and Party D. Vista submitted a revised bid of $35.25 per share and requested that Marketo enter into exclusive negotiations with Vista. Party D's revised bid was at $35.05 per share. In its revised bid, Party D re-indicated that its bid was contingent on completing confirmatory due diligence, which it expected it could complete in one week. Party D also requested additional further access to and meetings with Marketo management to finalize its operational plan.

        Later in the day on May 25, 2016, the Transaction Committee held another special meeting with members of Marketo management and representatives of Morgan Stanley and Wilson Sonsini. Morgan Stanley updated the Transaction Committee on the revised indications of interest Marketo had received from Vista and Party D. A representative of Morgan Stanley indicated that he believed, based on discussions with Vista and Party D, that Vista would not be able to go higher than its current price of $35.25 per share and that Party D indicated that it may have some room to move higher than $35.05 per share, but unlike Vista it also had remaining business due diligence items which if not confirmed could cause its indication of interest to move lower. The representative of Morgan Stanley also indicated that Vista's willingness to bid at $35.25 was tied to the limited exclusivity relative to Party D

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that was offered to both bidders. Representatives of Morgan Stanley and Wilson Sonsini led the Transaction Committee through a discussion regarding the key differences between Vista and Party D's final offers, including, among other things that Party D had proposed a termination fee of 2.70%, compared to a 3.50% termination fee proposed by Vista. Morgan Stanley also updated the Transaction Committee on the status of discussions with Party H, indicating that Morgan Stanley had attempted to reach a representative of Party H, but had not received a response from Party H at this time. The Transaction Committee instructed Morgan Stanley to inform Vista that, provided Vista would agree to certain material terms in the definitive agreement, including a reduction of the termination fee to 2.75%, Marketo was prepared to enter into a limited form of exclusivity with Vista to finalize the Merger Agreement and the related transaction documents. Near the end of the meeting, representatives of Morgan Stanley then left the meeting, and the Transaction Committee met in executive session with members of management and Wilson Sonsini. Subsequently, all members of management left the meeting, and the Transaction Committee met in an executive session with the representatives of Wilson Sonsini.

        In determining that it was appropriate and in the best interests of the Company to enter into limited exclusivity with Vista at such time, the Board of Directors considered, among other things, the fact that prior to entering into exclusivity with Vista, as part of its market check process, Marketo and Morgan Stanley had solicited six potential strategic parties and three potential financial sponsors as described above. In addition, throughout the process, the Board of Directors had also considered whether to initiate discussions with a limited number of additional strategic parties who are also competitors of Marketo. The Board of Directors considered the risk that reaching out to such competitors may harm Marketo's commercial prospects. It also considered the fact that these strategic parties had not reached out to Marketo regarding a potential acquisition, even after news outlets reported that Marketo was working with Morgan Stanley on a strategic review process on May 10, 2016. Morgan Stanley conducted several informal meetings with key representatives of the strategic parties after May 10, 2016, and the prospect of a transaction with Marketo was not discussed. The Board of Directors ultimately made the judgment that these strategic parties had been given sufficient opportunity to approach Marketo regarding an acquisition if they were interested, and, in light of the strategic and commercial risks of doing so, determined that Marketo should not approach them regarding a potential acquisition.

        On the evening of May 25, 2016, representatives of Morgan Stanley communicated to a representative of Vista that, as between existing parties who had made offers, it had the higher offer and that Marketo would grant Vista exclusivity through May 27, 2016, provided it agreed to certain revised terms in the definitive agreement draft it submitted, and that such exclusivity would only be related to those parties who had made a formal bid to Marketo.

        On May 25, 2016, Marketo and Vista entered into a limited exclusivity agreement through May 27, 2016, which enabled Marketo to continue discussions with the parties who had not yet made a proposal. Morgan Stanley subsequently communicated to each of Party H and Party E that time was of the essence and they would need to make a final decision in the next two days.

        On May 27, 2016, a representative of Party H communicated with a representative of Morgan Stanley to indicate that Party H was not interested in pursuing as acquisition at this time. On the same day, a representative of Party E communicated to a representative of Morgan Stanley that it would not be submitting an offer to acquire Marketo.

        Between the night of May 25, 2016 and May 27, 2016, representatives of Wilson Sonsini and Kirkland & Ellis LLP, legal counsel to Vista, worked to resolve the remaining open issues in the Merger Agreement and the various ancillary transaction documents.

        On May 27, 2016, the Board of Directors held a special meeting to consider the terms of the proposed transaction with members of Marketo's management and representatives of Morgan Stanley

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and Wilson Sonsini in attendance. A representative of Wilson Sonsini addressed the Board of Directors' fiduciary duties in connection with the sale of Marketo and then reviewed the terms of the draft Merger Agreement circulated prior to the Board of Directors meeting, including the resolution of the open issues, and reviewed certain other matters. Representatives of Morgan Stanley then reviewed its financial analysis and then delivered to the Board of Directors its oral opinion, subsequently confirmed in writing, that as of May 27, 2016, and based upon and subject to the assumptions made, procedures followed, matters considered and qualifications and limitations on the scope of review undertaken by Morgan Stanley as set forth in the written opinion, the consideration to be received by the holders of shares of our common stock (other than Excluded Shares) pursuant to the Merger Agreement was fair from a financial point of view to such holders. For more information about Morgan Stanley's opinion, see below under the caption "The Merger—Fairness Opinion of Morgan Stanley & Co. LLC." The representatives of Morgan Stanley then left the meeting, and the Board of Directors met in an executive session with members of management and the representatives of Wilson Sonsini. The Board of Directors further discussed the terms of the proposed offer from Vista and the sufficiency of the strategic review process. Subsequently, all members of management left the meeting, and the independent directors of the Board of Directors met in an executive session with the representatives of Wilson Sonsini. After a discussion with Wilson Sonsini regarding the strategic review process, the members of management rejoined the meeting. After discussing potential reasons for and against the proposed transaction (see below under the caption "The Merger—Recommendation of the Board of Directors and Reasons for the Merger"), the Board of Directors unanimously determined that the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement were fair to, advisable and in the best interests of Marketo and its stockholders. The Board of Directors therefore unanimously adopted and approved the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement and recommended that Marketo's stockholders vote to approve the Merger Agreement at any meeting of the stockholders to be called for the purposes of acting thereon.

        On the evening of May 27, 2016, the parties executed the Merger Agreement and the related agreements in connection with the transaction, and issued a joint press release on the morning of May 31, 2016, prior to the opening of the stock markets in the United States, announcing the transaction.

Recommendation of the Board of Directors and Reasons for the Merger

Recommendation of the Board of Directors

        The Board of Directors has unanimously: (1) determined that the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement are fair to, advisable and in the best interests of Marketo and its stockholders; and (2) adopted and approved the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement.

        The Board of Directors unanimously recommends that you vote: (1) "FOR" the adoption the Merger Agreement; and (2) "FOR" the adjournment of the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting.

Reasons for the Merger

        In evaluating the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement, the Board of Directors consulted with the Marketo management, its financial advisor and its outside legal counsel. In recommending that stockholders vote in favor of adoption of

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the Merger Agreement, the Board of Directors considered a number of factors, including the following (which factors are not necessarily presented in order of relative importance):

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The Board of Directors' belief that the all-cash Per Share Merger Consideration provides certainty of value and liquidity to stockholders, while eliminating the effect of long-term business and execution risk to stockholders.



•

The relationship of the Per Share Merger Consideration to the trading price of the common stock, including that the Per Share Merger Consideration constituted a premium of:



•

approximately 64% to the unaffected closing price of the common stock on May 9, 2016, the last full trading day prior to public reports that Marketo engaged Morgan Stanley to explore strategic alternatives, including a potential sale; and



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approximately 67% to the average closing market price of the common stock for the thirty trading day period ending on May 9, 2016, the last full trading day prior to public reports that Marketo engaged Morgan Stanley to explore strategic alternatives, including a potential sale.



•

The Board of Directors' belief that, based on negotiations and discussions with Vista, the Per Share Merger Consideration represented the highest price that Vista was willing to pay and the highest price per share value reasonably obtainable, each as of the date of the Merger Agreement.



•

The Board of Directors' understanding of Marketo's business and operations, and its current and historical results of operations, financial prospects and condition, including, more generally, the present competitive environment and business climate of the SaaS industry.



•

The perceived risks and benefits of a variety of strategic alternatives for Marketo, including: (1) the continuation of Marketo's business plan as an independent enterprise; (2) modifications to Marketo's strategy; (3) potential expansion opportunities into new business lines through acquisitions and combinations of Marketo with other businesses; and (4) the competitive landscape and the dynamics of the market for Marketo's products and technology.



•

The assessment that other alternatives were not reasonably likely to create greater value for stockholders than the Merger, taking into account execution risks as well as business, competitive, industry and market risks.



•

The multiples to revenues implied by the Per Share Merger Consideration.



•

The Board of Directors' consideration of Marketo's strategic and financial alternatives, including that:



•

Nine different parties and potential buyers were solicited during the process, including six strategic buyers and three private equity sponsors, in an effort to obtain the best value reasonably available to stockholders;



•

Of these bidders, only Vista and Party D made final bids to acquire Marketo;



•

Of the parties that made final bids to acquire Marketo, only Vista required no additional time for due diligence; and



•

Of the parties that made final bids to acquire Marketo, none made a final bid equal to or in excess of the Per Share Merger Consideration.



•

The risk that a prolonged strategic review process could have resulted in the loss of a favorable opportunity to successfully consummate the transaction with Vista, and was unlikely to yield a proposal that would be a material improvement to Vista's proposal.

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•

The oral opinion of Morgan Stanley, subsequently confirmed in writing, delivered to the Board of Directors that, as of May 27, 2016 and based upon and subject to the factors, assumptions, considerations, limitations and other matters set forth in its opinion, the consideration to be received by the holders of shares of Marketo common stock (other than Excluded Shares, which include, for example, shares of common stock owned by stockholders who have properly and validly exercised their statutory rights of appraisal under Section 262 of the DGCL), pursuant to the Merger Agreement was fair from a financial point of view to such holders. The full text of the written opinion is attached as Annex B to this proxy statement and is incorporated by reference in this proxy statement in its entirety. The opinion of Morgan Stanley is more fully described below under the caption "The Merger—Fairness Opinion of Morgan Stanley & Co. LLC."



•

The Management Projections, prepared by our management and more fully described below under the caption "The Merger—Marketo Financial Projections." The Management Projections were also provided to Morgan Stanley for the purposes of the opinion described in the preceding paragraph.



•

The terms of the Merger Agreement and the related agreements, including:



•

That the equity financing contemplated by the Equity Commitment Letter provided in favor of Parent was sufficient to fund the aggregate purchase price and the other payments contemplated by the Merger Agreement, and that Marketo is a named third party beneficiary of the Equity Commitment Letter;



•

The ability of the parties to consummate the Merger, including the fact that Parent's obligation to complete the Merger is not conditioned upon, nor limited by, the receipt of third-party debt financing;



•

Marketo's entitlement to specific performance to cause the equity financing contemplated by the Equity Commitment Letter to be funded, whether or not Vista is able to procure any debt to finance the transaction;



•

Marketo's ability, under certain circumstances, to furnish information to and conduct negotiations with third parties regarding Acquisition Proposals;



•

Marketo's ability to terminate the Merger Agreement in order to accept a Superior Proposal, subject to paying Parent a termination fee of $49.2 million and other conditions of the Merger Agreement;



•

The fact that the Board of Directors believed that the termination fee of $49.2 million, which is approximately 2.75% of Marketo's implied equity value in the Merger, is reasonable, below the market averages for such fees, and not preclusive of other offers;



•

Marketo's entitlement to specific performance to prevent breaches of the Merger Agreement;



•

The likelihood of satisfying the conditions to complete the Merger and the likelihood that the Merger will be completed;



•

The Board of Directors' view that the Merger Agreement (1) was the product of arms'-length negotiations, (2) contained terms and conditions which were favorable to Marketo and (3) was the result of a competitive solicitation process; and



•

The fact that Vista Fund VI provided a limited guaranty in favor of Marketo that guarantees the payment of all of the liabilities and obligations of Parent and Merger Sub under the Merger Agreement, subject to an aggregate cap equal to $116.3 million plus the

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Reimbursement Obligations (as described in the below section captioned "The Merger—Financing of the Merger").

•

The Board of Directors' view that the terms of the Merger Agreement would be unlikely to deter interested third parties from making a Superior Proposal, including the Merger Agreement's terms and conditions as they relate to changes in the recommendation of the Board of Directors and the belief that the termination fee potentially payable to Parent is reasonable in light of the circumstances, consistent with comparable transactions and not preclusive of other offers (see the sections captioned "Proposal 1: Adoption of the Merger Agreement—No Solicitation of Other Offers " and "Proposal 1: Adoption of the Merger Agreement—The Board of Directors' Recommendation; Company Board Recommendation Changes").

        The Board of Directors also considered a number of uncertainties and risks concerning the Merger, including the following (which factors are not necessarily presented in order of relative importance):

•

The risks and costs to Marketo if the Merger does not close, including the diversion of management and employee attention, and the potential effect on our business and relationships with customers and suppliers.



•

The fact that stockholders will not participate in any future earnings or growth of Marketo and will not benefit from any appreciations in value of Marketo, including any appreciation in value that could be realized as a result of improvements to our operations or future strategic or other transactions by Marketo.



•

The requirement that Marketo pay Parent a termination fee of $49.2 million under certain circumstances following termination of the Merger Agreement, including if the Board of Directors terminates the Merger Agreement to accept a Superior Proposal.



•

The restrictions on the conduct of Marketo's business prior to the consummation of the Merger, including the requirement that we conduct our business in the ordinary course, subject to specific limitations, which may delay or prevent Marketo from undertaking business opportunities that may arise before the completion of the Merger and that, absent the Merger Agreement, Marketo might have pursued.



•

The fact that an all cash transaction would be taxable to Marketo's stockholders that are U.S. persons for U.S. federal income tax purposes.



•

The fact that under the terms of the Merger Agreement, Marketo is unable to solicit other Acquisition Proposals during the pendency of the Merger.



•

The significant costs involved in connection with entering into the Merger Agreement and completing the Merger (many of which are payable whether or not the Merger is consummated) and the substantial time and effort of Marketo management required to complete the Merger, which may disrupt our business operations.



•

The fact that Marketo's business, sales operations and financial results could suffer in the event that the Merger is not consummated.



•

The risk that the Merger might not be completed and the effect of the resulting public announcement of termination of the Merger Agreement on the trading price of the common stock.



•

The fact that the completion of the Merger will require antitrust clearance in the United States.



•

The fact that Marketo's directors and officers may have interests in the Merger that may be different from, or in addition to, those of Marketo's stockholders (see below under the caption "The Merger—Interests of Marketo's Directors and Executive Officers in the Merger").

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•

The fact that the announcement and pendency of the Merger, or the failure to complete the Merger, may cause substantial harm to Marketo's relationships with its employees (including making it more difficult to attract and retain key personnel and the possible loss of key management, technical, sales and other personnel), vendors and customers and may divert employees' attention away from Marketo's day-to-day business operations.

        The foregoing discussion is not meant to be exhaustive, but summarizes the material factors considered by the Board of Directors in its consideration of the Merger. After considering these and other factors, the Board of Directors concluded that the potential benefits of the Merger outweighed the uncertainties and risks. In view of the variety of factors considered by the Board of Directors and the complexity of these factors, the Board of Directors did not find it practicable to, and did not, quantify or otherwise assign relative weights to the foregoing factors in reaching its determination and recommendations. Moreover, each member of the Board of Directors applied his or her own personal business judgment to the process and may have assigned different weights to different factors. The Board of Directors unanimously adopted and approved the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement and recommends that stockholders adopt the Merger Agreement based upon the totality of the information presented to and considered by the Board of Directors.

Fairness Opinion of Morgan Stanley & Co. LLC

        Marketo retained Morgan Stanley to provide it with financial advisory services and a financial opinion in connection with the possible sale of Marketo. The Board of Directors selected Morgan Stanley to act as Marketo's financial advisor based on Morgan Stanley's qualifications, expertise and reputation, its knowledge of and involvement in recent transactions in the SaaS industry, and its knowledge and understanding of Marketo's business and affairs. At the meeting of the Board of Directors on May 27, 2016, Morgan Stanley rendered to the Board of Directors its oral opinion, subsequently confirmed in writing, that as of May 27, 2016, and based upon and subject to the assumptions made, procedures followed, matters considered and qualifications and limitations on the scope of review undertaken, by Morgan Stanley, as set forth in its written opinion, the consideration to be received by the holders of shares of Marketo common stock (other than Excluded Shares, which include, for example, shares of common stock owned by stockholders who have properly and validly exercised their statutory rights of appraisal under Section 262 of the DGCL), pursuant to the Merger Agreement, was fair from a financial point of view to such stockholders.

        The full text of the written opinion of Morgan Stanley to the Board of Directors, dated as of May 27, 2016, which sets forth, among other things, the assumptions made, procedures followed, matters considered and qualifications and limitations on the scope of the review undertaken, by Morgan Stanley in rendering its opinion, is attached as Annex B to this proxy statement and is incorporated by reference in this proxy statement in its entirety. The summary of the opinion of Morgan Stanley in this proxy statement is qualified in its entirety by reference to the full text of the opinion. You should carefully read and consider Morgan Stanley's entire written opinion, as it contains important information. Morgan Stanley's opinion was directed to the Board of Directors, in its capacity as such, and addresses only the fairness from a financial point of view of the consideration to be received by the holders of shares of Marketo common stock (other than Excluded Shares, which include, for example, shares of common stock owned by stockholders who have properly and validly exercised their statutory rights of appraisal under Section 262 of the DGCL), pursuant to the Merger Agreement and as of the date of the opinion, and does not address any other aspects or implications of the Merger or related transactions. Morgan Stanley's opinion was not intended to, and does not, constitute advice or a recommendation as to how our stockholders should vote at any stockholders' meeting that may be held in connection with the Merger or whether the stockholders should take any

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other action in connection with the Merger. The summary of the opinion of Morgan Stanley set forth below is qualified in its entirety by reference to the full text of the opinion.

        In connection with rendering its opinion, Morgan Stanley, among other things:

•

reviewed certain publicly available financial statements and other business and financial information of Marketo;



•

reviewed certain internal financial statements and other financial and operating data concerning Marketo;



•

reviewed certain financial projections prepared by the management of Marketo;



•

discussed the past and current operations and financial condition and the prospects of Marketo with senior executives of Marketo;



•

reviewed the reported prices and trading activity for Marketo common stock;



•

compared Marketo's financial performance and the prices and trading activity of Marketo's common stock with that of certain other publicly-traded companies comparable with Marketo, and their securities;



•

reviewed the financial terms, to the extent publicly available, of certain comparable acquisition transactions;



•

participated in certain discussions and negotiations among representatives of Marketo and Parent and their financial and legal advisors;



•

reviewed the Merger Agreement and certain related documents; and



•

performed such other analyses, reviewed such other information and considered such other factors as Morgan Stanley deemed appropriate.

        In arriving at its opinion, Morgan Stanley assumed and relied upon, without independent verification, the accuracy and completeness of the information that was publicly available or supplied or otherwise made available to Morgan Stanley by Marketo, and which formed a substantial basis for its opinion. Morgan Stanley further relied upon the assurances of Marketo management that it was not aware of any facts or circumstances that would make such information inaccurate or misleading. With respect to the financial projections, Morgan Stanley assumed that they had been reasonably prepared on bases reflecting the best currently available estimates and judgments of Marketo management of the future financial performance of Marketo. In addition, Morgan Stanley assumed that the Merger will be consummated in accordance with the terms set forth in the Merger Agreement without any waiver, amendment or delay of any terms or conditions and that the definitive Merger Agreement would not differ in any material respect from the draft furnished to Morgan Stanley. Morgan Stanley assumed that, in connection with the receipt of all the necessary governmental, regulatory or other approvals and consents required for the proposed merger, no delays, limitations, conditions or restrictions will be imposed that would have a material adverse effect on the contemplated benefits expected to be derived in the proposed merger. Morgan Stanley is not a legal, tax or regulatory advisor. Morgan Stanley is a financial advisor only and relied upon, without independent verification, the assessment of Marketo and its legal, tax or regulatory advisors with respect to legal, tax or regulatory matters. Morgan Stanley expressed no opinion with respect to the fairness of the amount or nature of the compensation to be paid to any Marketo officers, directors or employees, or any class of such persons, relative to the consideration to be received by the holders of shares of Marketo common stock in the Merger. Morgan Stanley did not make any independent valuation or appraisal of Marketo's assets or liabilities, nor was Morgan Stanley furnished with any such valuations or appraisals. Morgan Stanley's opinion was necessarily based on financial, economic, market, and other conditions as in effect on, and the information made available to Morgan Stanley as of, May 27, 2016. Events occurring after May 27,

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2016 may affect Morgan Stanley's opinion and the assumptions used in preparing it, and Morgan Stanley did not assume any obligation to update, revise or reaffirm its opinion.

Summary of Financial Analyses

        The following is a brief summary of the material analyses performed by Morgan Stanley in connection with its oral opinion and the preparation of its written opinion letter dated May 27, 2016 to the Board of Directors. The following summary is not a complete description of Morgan Stanley's opinion or the financial analyses performed and factors considered by Morgan Stanley in connection with its opinion, nor does the order of analyses described represent the relative importance or weight given to those analyses. Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before May 27, 2016, the last full trading day prior to the meeting of the Board of Directors to approve and adopt the Merger Agreement, declare the advisability of the Merger Agreement and approve the transactions contemplated thereby, including the Merger. The various analyses summarized below were based on the closing price of $21.47 per share of Marketo common stock as of May 9, 2016 (the last full trading day prior to public reports that Marketo engaged Morgan Stanley to explore strategic alternatives, including a potential sale), and are not necessarily indicative of current market conditions. Some of these summaries of financial analyses include information presented in tabular format. In order to fully understand the financial analyses used by Morgan Stanley, the tables must be read together with the text of each summary. The tables alone do not constitute a complete description of the financial analyses. The analyses listed in the tables and described below must be considered as a whole; considering any portion of such analyses and of the factors considered, without considering all analyses and factors, could create a misleading or incomplete view of the process underlying Morgan Stanley's opinion.

        In performing the financial analysis summarized below and arriving at its opinion, Morgan Stanley used and relied upon certain financial projections provided by Marketo's management and referred to in this proxy statement (and defined in the following section captioned, "The Merger—Marketo Financial Projections") as the "Higher Growth Case" and the "Leveraged Growth Case," and, together, the "Management Projections," and certain financial projections based on Wall Street research reports and referred to in this proxy statement as the "Street Case." For more information, please see the section of this proxy statement captioned, "The Merger—Marketo Financial Projections."

Public Trading Comparables Analysis

        Morgan Stanley performed a public trading comparables analysis, which attempts to provide an implied value of a company by comparing it to similar companies that are publicly traded. Morgan Stanley reviewed and compared certain financial estimates for Marketo with comparable publicly available consensus equity analyst research estimates for companies, selected based on Morgan Stanley's professional judgment and experience, that share similar business characteristics and have certain comparable operating characteristics including, among other things, similarly sized revenue and/or revenue growth rates, market capitalizations, profitability, scale and/or other similar operating characteristics (we refer to these companies as the comparable companies). These companies were the following:

•

Cornerstone OnDemand Inc.



•

Cvent, Inc.



•

Demandware, Inc.



•

HubSpot, Inc.



•

NetSuite Inc.

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•

New Relic, Inc.



•

RingCentral, Inc.



•

Salesforce.com, Inc.



•

Tableau Software, Inc.



•

Zendesk, Inc.

        For purposes of this analysis, Morgan Stanley analyzed the ratio of aggregate value, which Morgan Stanley defined as fully-diluted market capitalization plus total debt, plus non-controlling interest, less cash and cash equivalents, to revenue.

        Based on its analysis of the relevant metrics for each of the comparable companies and upon the application of its professional judgment and experience, Morgan Stanley selected representative ranges of revenue multiples and applied these ranges of multiples to the estimated 2016 and 2017 revenue for Marketo, based on the Street Case and Management Projections. With respect to Cvent, Morgan Stanley's analysis utilized a price per share for Cvent as of prior to its publicly announced acquisition by Vista Equity Partners.

        Based on the outstanding shares of Marketo common stock on a fully-diluted basis (including outstanding options, performance stock units and restricted stock units) on May 24, 2016, as provided by Marketo management, Morgan Stanley calculated the estimated implied value per share of Marketo's common stock as of May 27, 2016 as follows:

        No company utilized in the public trading comparables analysis is identical to Marketo. In evaluating the comparable companies, Morgan Stanley made numerous assumptions with respect to industry performance, general business, regulatory, economic, market and financial conditions and other matters, many of which are beyond Marketo's control. These include, among other things, the impact of competition on Marketo's business and the industry generally, industry growth, and the absence of any adverse material change in the financial condition and prospects of Marketo and the industry, and in the financial markets in general. Mathematical analysis (such as determining the average or median) is not in itself a meaningful method of using comparable company data.

Discounted Equity Value Analysis

        Morgan Stanley performed a discounted equity value analysis, which is designed to provide insight into the potential future equity value of Marketo as a function of Marketo's estimated future revenues. The resulting equity value is subsequently discounted to arrive at an estimate of the implied present value. In connection with this analysis, Morgan Stanley calculated a range of implied present equity values per share of common stock on a standalone basis. The discounted equity value using the Management Projections was calculated using revenue projections provided by Marketo management

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for calendar year 2018. In addition, Morgan Stanley calculated the discounted equity value using the Street Case. In analyzing the Street Case, Morgan Stanley used revenue estimates for calendar years 2016 and 2017 from publicly available Wall Street research available as of May 11, 2016, as well as extrapolations discussed with, and approved by, Marketo management for estimated revenue for calendar year 2018. Morgan Stanley then used the 2018 revenue estimates for the basis of the Street Case in this analysis. Based upon the application of its professional judgment and experience, Morgan Stanley applied a range of revenue multiples to the estimates of 2018 revenue from the Management Projections and Street Case and then applied a discount rate of 10.03%, which rate was selected based on Marketo's estimated cost of equity.

        The following table summarizes Morgan Stanley's analysis:

Discounted Cash Flow Analysis

        Morgan Stanley performed a discounted cash flow analysis, which is designed to provide an implied value of a company by calculating the present value of the estimated future cash flows and terminal value of such company. Morgan Stanley calculated a range of equity values per share for Marketo common stock based on a discounted cash flow analysis to value Marketo as a stand-alone entity. Morgan Stanley utilized estimates from the Management Projections and Street Case for purposes of its discounted cash flow analysis, as more fully described below.

        Morgan Stanley first calculated the estimated unlevered free cash flow which is defined as adjusted earnings before interest, taxes, depreciation and amortization, less (1) stock-based compensation expense, (2) taxes, and (3) capital expenditures, and plus changes in net working capital. The Management Projections estimates through 2019 were based on projections prepared by Marketo management, and the estimated unlevered free cash flow for calendar years 2020 through 2025 were based on extrapolations of such estimates discussed with, and approved by, Marketo management. The Street Case estimates through 2017 were based on publicly available Wall Street research available as of May 11, 2016, except for the changes in net working capital as a percentage of change in revenue assumptions through 2017, which were adjusted to be in line with Leveraged Growth Case. The estimated unlevered free cash flow projections for the Street Case for calendar years 2018 through 2025 were based on extrapolations discussed with, and approved by, Marketo's management. Morgan Stanley calculated the net present value of free cash flows for Marketo for the nine months ended December 31, 2016 through calendar year 2025. Based on the perpetual growth rates ranging from 2.5% to 3.5%, selected based upon the application of its professional judgment and experience, Morgan Stanley calculated terminal values in the year 2025. The free cash flows and terminal values were discounted to present values as of March 31, 2016 at a discount rate of 10.03%, which discount rate was selected, upon the application of Morgan Stanley's professional judgment and experience, to reflect an estimate of Marketo's weighted average cost of capital.

        Based on the outstanding shares on May 24, 2016 of Marketo common stock on a fully-diluted basis (including outstanding options, performance stock units and restricted stock units) as provided by

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Marketo management, Morgan Stanley calculated the estimated implied value per share of Marketo common stock as of March 31, 2016 as follows:

Precedent Transactions Analysis

        Morgan Stanley performed a precedent transactions analysis, which is designed to imply a value of a company based on publicly available financial terms and premia of selected transactions. Morgan Stanley compared publicly available statistics for, cloud and software transactions, selected based on Morgan Stanley's professional judgment and experience, with an equity value of greater than $1 billion occurring between 2010 and May 27, 2016 (the last full trading day prior to the meeting of the Board of Directors to approve and adopt the Merger Agreement, declare the advisability of the Merger Agreement and approve the transactions contemplated thereby, including the Merger). Morgan Stanley selected such comparable transactions because they shared certain characteristics with the Merger. The following is a list of the cloud and software transactions reviewed:

Selected Cloud and Software Transactions (Target / Acquiror):

Acme Packet, Inc. / Oracle Corporation
AirWatch LLC / VMware, Inc.
ArcSight Inc. / Hewlett-Packard Company
Ariba Inc. / SAP Corporation
Art Technology Group, Inc. / Oracle Corporation
Autonomy Corporation plc / Hewlett-Packard Company
Blackboard Inc. / Providence Equity Partners
Blue Coat Systems, Inc. / Bain Capital
Concur Technologies, Inc. / SAP Corporation
Constant Contact, Inc. / Endurance International Group Holdings, Inc.
Cvent Inc. / Vista Equity Partners
Dealertrack Technologies, Inc. / Cox Automotive, Inc.
Eclipsys Corporation / Allscripts Healthcare Solutions, Inc.
ExactTarget, Inc. / Salesforce.com, Inc.
Informatica Corporation / Permira Funds
Interactive Data Corporation / Silver Lake Partners and Warburg Pincus
JDA Software Group, Inc. / RedPrairie Corp.
Kenexa Corporation / International Business Machines Corporation
Lawson Software Inc. / Infor Global Solutions and Golden Gate Capital
Mandiant Corporation / FireEye, Inc.
McAfee, Inc. / Intel Corporation
Misys / Vista Equity Partners
Novell, Inc. / Attachmate Corporation
Quest Software, Inc. / Dell Inc.
Radiant Systems, Inc. / NCR Corporation
Responsys, Inc. / Oracle Corporation
RightNow Technologies, Inc. / Oracle Corporation
Skillsoft PLC / Berkshire Partners LLC, Advent International Corporation and Bain Capital Partners, LLC

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SolarWinds, Inc. / Silver Lake Partners and Thoma Bravo, LLC
Solera Holdings, Inc. / Vista Equity Partners
SonicWALL, Inc. / Dell Inc.
Sourcefire, Inc. / Cisco Systems, Inc.
SuccessFactors, Inc. / SAP Corporation
SunGard Data Systems Inc. / Fidelity National Information Services Inc.
Sybase Inc. / SAP Corporation
Taleo Corporation / Oracle Corporation
VeriSign, Inc. / Symantec Corp.

        For the transactions listed above, Morgan Stanley noted the multiple of aggregate value of the transaction to next twelve months revenue.

        Morgan Stanley reviewed the same group of select precedent transactions described above that involved publicly listed companies, and excluding private company targets, occurring between 2010 and May 27, 2016 (the last full trading day prior to the meeting of the Board of Directors to approve and adopt the Merger Agreement, declare the advisability of the Merger Agreement and approve the transactions contemplated thereby, including the Merger). For these transactions, Morgan Stanley noted the distributions of the following financial statistics: (1) the implied premium to the acquired company's closing share price on the last trading day prior to announcement (or the last trading day prior to the share price being affected by acquisition rumors or similar merger-related news); and (2) the implied premium to the acquired company's 30-trading-day average closing share price prior to announcement (or the last 30-trading-day average closing share price prior to the share price being affected by acquisition rumors or similar merger-related news).

        Based on its analysis of the relevant metrics and time frame for each of the transactions listed above and upon the application of its professional judgment and experience, Morgan Stanley selected representative ranges of implied premia and financial multiples of the transactions and applied these ranges of premia and financial multiples to the relevant financial statistic for Marketo. The selected representative ranges of implied premia were based on the 25th percentile and 75th percentile of the respective premia from the group of select public precedent transactions described above. The following table summarizes Morgan Stanley's analysis:

        Morgan Stanley noted that the consideration to be received by holders of shares of Marketo common stock (other than Excluded Shares, which include, for example, shares of common stock owned by stockholders who have properly and validly exercised their statutory rights of appraisal under Section 262 of the DGCL) pursuant to the Merger Agreement is $35.25 per share.

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        No company or transaction utilized in the precedent transactions analysis is identical to Marketo or the Merger. In evaluating the precedent transactions, Morgan Stanley made numerous assumptions with respect to industry performance, general business, regulatory, economic, market and financial conditions and other matters, many of which are beyond Marketo's control. These include, among other things, the impact of competition on Marketo's business and the industry generally, industry growth, and the absence of any adverse material change in the financial condition and prospects of Marketo and the industry, and in the financial markets in general, which could affect the public trading value of the companies and the aggregate value and equity value of the transactions to which they are being compared. The fact that points in the range of implied present value per share of Marketo derived from the valuation of precedent transactions were less than or greater than the consideration is not necessarily dispositive in connection with Morgan Stanley's analysis of the consideration for the Merger, but one of many factors Morgan Stanley considered.

Other Information

        Morgan Stanley observed additional factors that were not considered part of Morgan Stanley's financial analysis with respect to its opinion, but which were noted as reference data for the Board of Directors, including the following information described under the sections titled "Trading Range" and "Equity Research Analysts' Future Price Targets."

Trading Range

        Morgan Stanley noted the trading range with respect to the historical share prices of Marketo common stock. Morgan Stanley reviewed the range of closing prices of Marketo common stock for various periods ending on May 9, 2016, the last full trading day prior to public reports that Marketo engaged Morgan Stanley to explore strategic alternatives, including a potential sale. Morgan Stanley observed the following:

        Morgan Stanley observed that Marketo common stock closed at $21.47 on May 9, 2016. Morgan Stanley noted that the consideration per share of Marketo common stock of $35.25 pursuant to the Merger Agreement reflected a 64.2% premium to the closing price per share of Marketo common stock on May 9, 2016 and a 67.3% premium to the average closing price per share of Marketo common stock for the 30-trading-days prior to and including May 9, 2016.

Equity Research Analysts' Future Price Targets

        Morgan Stanley reviewed future public market trading price targets for Marketo common stock prepared and published by equity research analysts prior to May 27, 2016 (the last full trading day prior to the meeting of the Board of Directors to approve and adopt the Merger Agreement, declare the advisability of the Merger Agreement and approve the transactions contemplated thereby, including the Merger). These one-year forward targets reflected each analyst's estimate of the future public market trading price of Marketo common stock. The 25th percentile and 75th percentile of undiscounted analyst price targets for Marketo common stock was $26.00 and $35.00 per share as of May 27, 2016. The 25th percentile and 75th percentile of analyst price targets per share of Marketo common stock discounted for one year at a rate of 10.03%, selected by Morgan Stanley, upon the application of its professional judgment, to reflect Marketo's cost of equity, was $23.63 to $31.81 per share as of May 27, 2016.

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        The public market trading price targets published by equity research analysts do not necessarily reflect current market trading prices for Marketo common stock, and these estimates are subject to uncertainties, including the future financial performance of Marketo and future financial market conditions.

General

        In connection with the review of the Merger by the Board of Directors, Morgan Stanley performed a variety of financial and comparative analyses for purposes of rendering its opinion. The preparation of a financial opinion is a complex process and is not necessarily susceptible to a partial analysis or summary description. In arriving at its opinion, Morgan Stanley considered the results of all of its analyses as a whole and did not attribute any particular weight to any analysis or factor it considered. Morgan Stanley believes that selecting any portion of its analyses, without considering all analyses as a whole, would create an incomplete view of the process underlying its analyses and opinion. In addition, Morgan Stanley may have given various analyses and factors more or less weight than other analyses and factors, and may have deemed various assumptions more or less probable than other assumptions. As a result, the ranges of valuations resulting from any particular analysis described above should not be taken to be Morgan Stanley's view of the actual value of Marketo. In performing its analyses, Morgan Stanley made numerous assumptions with respect to industry performance, general business, regulatory, economic, market and financial conditions and other matters, many of which are beyond Marketo's control. These include, among other things, the impact of competition on Marketo's business and the industry generally, industry growth, and the absence of any adverse material change in the financial condition and prospects of Marketo and the industry, and in the financial markets in general. Any estimates contained in Morgan Stanley's analyses are not necessarily indicative of future results or actual values, which may be significantly more or less favorable than those suggested by such estimates.

        Morgan Stanley conducted the analyses described above solely as part of its analysis of the fairness from a financial point of view of the consideration to be received by the holders of shares of Marketo common stock (other than Excluded Shares, which include, for example, shares of common stock owned by stockholders who have properly and validly exercised their statutory rights of appraisal under Section 262 of the DGCL) pursuant to the Merger Agreement and in connection with the delivery of its opinion, dated May 27, 2016, to the Board of Directors. These analyses do not purport to be appraisals or to reflect the prices at which shares of Marketo common stock might actually trade.

        The consideration to be received by the holders of shares of Marketo common stock (other than Excluded Shares, which include, for example, shares of common stock owned by stockholders who have properly and validly exercised their statutory rights of appraisal under Section 262 of the DGCL) pursuant to the Merger Agreement was determined through arm's-length negotiations between Marketo and Parent and was approved by the Board of Directors. Morgan Stanley provided advice to the Board of Directors during these negotiations but did not, however, recommend any specific consideration to Marketo or the Board of Directors, nor did Morgan Stanley opine that any specific consideration constituted the only appropriate consideration for the Merger. Morgan Stanley's opinion did not address the relative merits of the Merger as compared to any other alternative business transaction, or other alternatives, or whether or not such alternatives could be achieved or are available. Morgan Stanley's opinion was not intended to, and does not, constitute advice or a recommendation as to how Marketo stockholders should vote at any stockholders' meeting that may be held in connection with the Merger, or whether the stockholders should take any other action in connection with the Merger.

        Morgan Stanley's opinion and its presentation to the Board of Directors was one of many factors taken into consideration by the Board of Directors in deciding to approve and adopt the Merger Agreement, declare the advisability of the Merger Agreement and approve the transactions contemplated thereby, including the Merger. Consequently, the analyses as described above should not be viewed as determinative of the opinion of the Board of Directors with respect to the consideration

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pursuant to the Merger Agreement or of whether the Board of Directors would have been willing to agree to different consideration. Morgan Stanley's opinion was approved by a committee of Morgan Stanley investment banking and other professionals in accordance with Morgan Stanley's customary practice.

        The Board of Directors retained Morgan Stanley based upon Morgan Stanley's qualifications, experience and expertise. Morgan Stanley is a global financial services firm engaged in the securities, investment management and individual wealth management businesses. Its securities business is engaged in securities underwriting, trading and brokerage activities, foreign exchange, commodities and derivatives trading, prime brokerage, as well as providing investment banking, financing and financial advisory services. Morgan Stanley, its affiliates, directors and officers may at any time invest on a principal basis or manage funds that invest, hold long or short positions, finance positions, and may trade or otherwise structure and effect transactions, for their own account or the accounts of its customers, in debt or equity securities or loans of the Parent, Marketo, Vista and its affiliated funds, including, but not limited to Vista Fund VI (Vista, together with Vista Fund VI, and each of their respective affiliated funds, collectively, the "Vista Entities") or any other company, or any currency or commodity, that may be involved in the Merger, or any related derivative instrument.

        Under the terms of its engagement letter, Morgan Stanley provided Marketo financial advisory services and a financial opinion, described in this section and attached to this proxy statement as Annex B, in connection with the Merger, and Marketo has agreed to pay Morgan Stanley a fee of approximately $27.1 million for its services, approximately $24.1 million of which is contingent upon the closing of the Merger, and $3.0 million of which was due and payable upon the execution of the Merger Agreement. Marketo has also agreed to reimburse Morgan Stanley for its reasonable expenses, including fees of outside counsel and other professional advisors, incurred in connection with its engagement. In addition, Marketo has agreed to indemnify Morgan Stanley and its affiliates, its and their respective directors, officers, agents and employees and each other person, if any, controlling Morgan Stanley or any of its affiliates against certain liabilities and expenses relating to, arising out of or in connection with Morgan Stanley's engagement.

        In the two years prior to the date of Morgan Stanley's opinion, Morgan Stanley and its affiliates have been engaged on financial advisory and financing assignments for the Vista Entities, including, Vista Fund VI, and have received approximately $24.6 million in fees for such services from the Vista Entities, including, Vista Fund VI, which, together with one or more of its affiliates, is the controlling stockholder of the Parent. In the two years prior to the date of Morgan Stanley's opinion, Morgan Stanley and its affiliates have not been engaged on any financial advisory or financing assignments for Marketo, and have not received any fees for such services from Marketo during such time. Morgan Stanley may seek to provide financial advisory or financing services to Marketo, the Parent, or the Vista Entities and each of their respective affiliates in the future and would expect to receive fees for the rendering of these services.

Marketo Financial Projections

        Marketo does not, as a matter of course, publicly disclose its projections of its future financial performance. However, early in April 2016, before Marketo had engaged in any discussions with any third parties regarding a potential transaction with Marketo, Marketo's management prepared two sets of financial projections, which were provided to the Board of Directors and Morgan Stanley on May 13, 2016 in connection with the strategic review process, as described in this proxy statement. The first set of financial projections, which we refer to as the "Leveraged Growth Case," assumed a revenue growth rate of 29%-31% with a faster path to profitability. The second set of financial projections, which we refer to as the "Higher Growth Case," assumed a higher revenue growth rate and profitability later in the period of the projections due to a significant investment in new customer acquisition and market share growth. Within each case, Marketo adjusted spend rates to reflect costs

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necessary to support and improve the health of the installed base and costs associated with new customer acquisition. We refer to the Leveraged Growth Case and the Higher Growth Case, together, as the "Management Projections."

        The Management Projections were the only financial forecasts with respect to Marketo provided by Marketo for use by Morgan Stanley in performing its financial analyses during the strategic review process. The Leveraged Growth Case was the only financial forecasts made available to the participants in the strategic review process in connection with their due diligence review.

        Summaries of the Management Projections are set forth below.

Higher Growth Case

        In connection with Morgan Stanley's financial analysis, Morgan Stanley extrapolated the financial projections reflected in the Higher Growth Case out to fiscal years 2020 to 2025, which extrapolations were discussed with, and approved by, Marketo management. The extrapolations, together with Morgan Stanley's derivation of unlevered free cash flow based on the Management Projections, which were also discussed with, and approved by, Marketo management, are set forth below.

Leveraged Growth Case

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        In connection with Morgan Stanley's financial analysis, Morgan Stanley extrapolated the financial projections reflected in the Leveraged Growth Case out to fiscal years 2020 to 2025, which extrapolations were discussed with, and approved by, Marketo management. The extrapolations, together with Morgan Stanley's derivation of unlevered free cash flow based on the Management Projections, which were also discussed with, and approved by, Marketo management, are set forth below.

Cautionary Statements Regarding Management Projections

        The Management Projections included in this proxy statement have been prepared by Marketo management. The Management Projections were not prepared with a view to public disclosure and are included in this proxy statement only because the Management Projections were made available to Morgan Stanley for use in connection with its financial analyses as described in this proxy statement and the Leveraged Growth Case were made available to Vista and other parties in connection with their due diligence review of Marketo. The Management Projections were not prepared with a view to compliance with (1) US Generally Accepted Accounting Principles ("GAAP"), (2) the published guidelines of the SEC regarding projections and forward-looking statements; or (3) the guidelines established by the American Institute of Certified Public Accountants for preparation and presentation of prospective financial information. Furthermore, KPMG, LLC, our independent registered public accountant, has not examined, reviewed, compiled or otherwise applied procedures to the Management Projections and, accordingly, assumes no responsibility for, and expresses no opinion on, them.

        The Management Projections are forward-looking statements. For information on factors that may cause Marketo's future results to materially vary, see the information under the section captioned "Forward-Looking Statements." In addition, although the Management Projections are presented with numerical specificity, they reflect numerous assumptions and estimates as to future events made by Marketo management that they believed were reasonable at the time the Management Projections were prepared, taking into account the relevant information available to Marketo management at the time. However, these assumptions and estimates are not fact, and the Management Projections should not be relied upon as being indicative of actual future results. Important factors that may affect actual results and cause the Management Projections not to be achieved include, among other things, general economic conditions, Marketo's ability to achieve forecasted sales, accuracy of certain accounting assumptions, changes in actual or projected cash flows, competitive pressures and changes in tax laws. In addition, the Management Projections do not take into account any circumstances or events occurring after the date that they were prepared and do not give effect to the Merger. As a result, there can be no assurance that the Management Projections will be realized, and actual results may be materially better or worse than those contained in the Management Projections. The Management Projections cover multiple years, and such information by its nature becomes less reliable with each successive year. The inclusion of the Management Projections in this proxy statement should not be regarded as an indication that the Board of Directors, Marketo, Morgan Stanley or any of their respective affiliates or Representatives or any other recipient of this information considered, or now considers, the Management Projections to be predictive of actual future results. The summary of the

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Management Projections is not included in this proxy statement in order to induce any stockholder to vote in favor of the proposal to adopt the Merger Agreement or any of the other proposals to be voted on at the Special Meeting. We do not intend to update or otherwise revise the Management Projections to reflect circumstances existing after the date when made or to reflect the occurrence of future events, even in the event that any or all of the assumptions underlying the Management Projections are shown to be in error or no longer appropriate. In light of the foregoing factors and the uncertainties inherent in the Management Projections, stockholders are cautioned not to place undue, if any, reliance on the projections included in this proxy statement.

        The Management Projections and the accompanying tables set forth above contain certain non-GAAP financial measures, including EBITDA and Cash EBITDA, which Marketo believes are helpful in understanding its past financial performance and future results. The non-GAAP financial measures are not meant to be considered in isolation or as a substitute for comparable GAAP measures and should be read in conjunction with Marketo's consolidated financial statements prepared in accordance with GAAP. Due to the forward-looking nature of the selected unaudited prospective financial information, specific quantifications of the amounts that would be required to reconcile it to GAAP measures are not available. Marketo management regularly uses Marketo's supplemental non-GAAP financial measures internally to understand and manage the business and forecast future periods.

        As referred to above, EBITDA and Cash EBITDA are financial measures commonly used in our industry but are not defined under GAAP. EBITDA represents income before interest, income taxes, depreciation and amortization, stock-based compensation and costs related to acquisitions. Cash EBITDA represents EBITDA plus changes in deferred revenue. Marketo believes that EBITDA and Cash EBITDA are performance measures that provides securities analysts, investors and other interested parties with a measure of operating results unaffected by differences in capital structures, capital investment cycles and ages of related assets among otherwise comparable companies in our industry. Marketo further believes that EBITDA and Cash EBITDA are frequently used by securities analysts, investors and other interested parties in their evaluation of companies, many of which present EBITDA and Cash EBITDA measures when reporting their results. Marketo believes that EBITDA and Cash EBITDA facilitates company-to-company operating performance comparisons by adjusting for potential differences caused by variations in capital structures (affecting net interest expense), taxation (such as the impact of differences in effective tax rates or net operating losses), and the age and book depreciation of facilities and equipment (affecting relative depreciation expense), which may vary for different companies for reasons unrelated to operating performance. EBITDA and Cash EBIDTA have limitations relative to net income, their most comparable GAAP financial measure, including that they are not necessarily comparable to other similarly titled financial measures of other companies due to the potential inconsistencies in the method of calculation.

Interests of Marketo's Directors and Executive Officers in the Merger

        When considering the recommendation of the Board of Directors that you vote to approve the proposal to adopt the Merger Agreement, you should be aware that our directors and executive officers may have interests in the Merger that are different from, or in addition to, the interests of stockholders generally, as more fully described below. The Board of Directors was aware of and considered these interests, among other matters, to the extent that they existed at the time, in approving the Merger Agreement and the Merger and recommending that the Merger Agreement be adopted by stockholders.

Arrangements with Parent

        As of the date of this proxy statement, none of our executive officers has entered into any agreement with Parent or any of its affiliates regarding employment with, or the right to purchase or

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participate in the equity of, the Surviving Corporation or one or more of its affiliates. Prior to or following the closing of the Merger, however, certain of our executive officers have had and may continue to have discussions, or may enter into agreements with, Parent or Merger Sub or their respective affiliates regarding employment with, or the right to purchase or participate in the equity of, the Surviving Corporation or one or more of its affiliates.

Insurance and Indemnification of Directors and Executive Officers

        The Surviving Corporation and Parent will indemnify, defend and hold harmless, and advance expenses to current or former directors, officers and employees of Marketo with respect to all acts or omissions by them in their capacities as such at any time prior to the Effective Time (including any matters arising in connection with the Merger Agreement or the transactions contemplated thereby), to the fullest extent that Marketo would be permitted by applicable law and to the fullest extent required by the organizational documents of Marketo or its subsidiaries as in effect on the date of the Merger Agreement. Parent will cause the certificate of incorporation, bylaws or other organizational documents of the Surviving Corporation and its subsidiaries to contain provisions with respect to indemnification, advancement of expenses and limitation of director, officer and employee liability that are no less favorable to the current or former directors, officers and employees of Marketo and its subsidiaries than those set forth in the Marketo's and its subsidiaries' organizational documents as of the date of the Merger Agreement. The Surviving Corporation and its subsidiaries will not, for a period of six years from the Effective Time, amend, repeal or otherwise modify these provisions in the organizational documents in any manner that would adversely affect the rights of the current or former directors, officers and employees of Marketo and its subsidiaries.

        The Merger Agreement also provides that prior to the Effective Time, Marketo may purchase a six-year prepaid "tail" policy on the same terms and conditions as Parent would be required to cause the Surviving Corporation and its subsidiaries to purchase as discussed below. Marketo's ability to purchase a "tail" policy is subject to a cap on the premium equal to 300% of the aggregate annual premiums currently paid by the Marketo for its existing directors' and officers' liability insurance and fiduciary insurance for its last full fiscal year. If Marketo does not purchase a "tail" policy prior to the Effective Time, for at least six years after the Effective Time, Parent will (1) cause the Surviving Corporation and its other subsidiaries to maintain in full force and effect, on terms and conditions no less advantageous to the current or former directors, officers and employees of Marketo and its subsidiaries, the existing directors' and officers' liability insurance and fiduciary insurance maintained by the Marketo as of the date of the Merger Agreement; and (2) not, and will not permit the Surviving Corporation or its other subsidiaries to, take any action that would prejudice the rights of, or otherwise impede recovery by, the beneficiaries of any such insurance, whether in respect of claims arising before or after the Effective Time. The "tail" policy will cover claims arising from facts, events, acts or omissions that occurred at or prior to the Effective Time, including the transactions contemplated in the Merger Agreement. The obligation of Parent or the Surviving Corporation, as applicable, is subject to an annual premium cap of 300% of the aggregate annual premiums currently paid by Marketo for such insurance, but Parent or the Surviving Corporation will purchase as much of such insurance coverage as possible for such amount. For more information, please see the section of this proxy statement captioned, "Proposal 1: Adoption of the Merger Agreement—Indemnification and Insurance."

Treatment of Equity-Based Awards

Treatment of Options

        As of the Record Date, there were 1,819,642 outstanding Options held by our directors and executive officers. At the Effective Time, and without any action required by any holder of an Option,

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each Option (or portion thereof) that is outstanding as of immediately prior to the Effective Time, whether vested or unvested:

(i)

with an exercise price per share less than $35.25, will be cancelled and converted into the right to receive an amount in cash equal to (a) the Per Share Merger Consideration (less the exercise price per share attributable to such Option), multiplied by (b) the total number of shares of common stock that are issuable upon the full exercise of such Option, minus (c) any applicable withholding taxes; and



(ii)

with an exercise price per share equal to or greater than $35.25, will be cancelled without payment of any consideration.

Treatment of Stock-Based Awards

        As of the Record Date, there were 806,794 outstanding Stock-Based Award Units held by our directors and executive officers. At the Effective Time, and without any action required by any holder of a Stock-Based Award, each Stock-Based Award that is outstanding as of immediately prior to the Effective Time, whether vested or unvested, will be cancelled and converted into the right to receive an amount equal to the (a) Per Share Merger Consideration (less the exercise price per share, if any, attributable to such stock-based award), multiplied by:

(i)

in the case of any Stock-Based Award that is only subject to time-vesting requirements, (b) the total number of shares of common stock that are subject to such Stock-Based Award, minus (c) any applicable withholding taxes; or



(ii)

in the case of any Stock-Based Award that is subject to time- and performance-vesting requirements, (b) the total number of shares of common stock determined pursuant to the "change in control" provisions of the award agreement underlying such Stock-Based Award (with the remaining time-vesting requirements deemed satisfied), minus (c) any applicable withholding taxes.

Payments Upon Termination Following Change-in-Control

Management Retention Agreements

        We are a party to a Management Retention Agreement with each of each of Phillip M. Fernandez (Marketo's Chairman of the Board and Chief Executive Officer), Brian K. Kinion (Marketo's Senior Vice President and Chief Financial Officer), Frederick A. Ball (Marketo's Executive Vice President and Chief Administrative Officer), Jason L. Holmes (Marketo's Executive Vice President and Chief Operating Officer), and Steven M. Winter (Marketo's Executive Vice President, Worldwide Field Operations). Each Management Retention Agreement provides that if, during the Change in Control Period, the executive officer's employment with us is terminated involuntarily by us without Cause and other than by his death or disability, or voluntarily by him for Good Reason (as such terms are defined in the Management Retention Agreement), then subject to the executive officer signing and not revoking a release in our favor, he will be entitled to the following: (i) a lump-sum severance payment equal to 100% (or in Mr. Fernandez's case, 150%) of his annual base salary (as in effect immediately prior to a Change in Control or his termination, whichever is greater) plus the greater of 100% (or in Mr. Fernandez's case, 150%) of his annual target bonus or 100% (or in Mr. Fernandez's case, 150%) of his most recent annual bonus; (ii) 100% acceleration of his equity compensation awards; and (iii) in lieu of any other employment benefits, $3,000 per month for 12 months (or in Mr. Fernandez's case, 18 months) from the date of termination.

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        For purposes of the Management Retention Agreements described above, the following definitions apply:

        "Cause" means (i) an unauthorized use or disclosure of our confidential information or trade secrets, which use or disclosure causes material harm to us; (ii) a deliberate material failure to comply with any of our written policies or rules; (iii) conviction of, or plea of "guilty" or "no contest" to, a felony under the laws of the U.S. or any state thereof; (iv) gross misconduct; (v) following a Change in Control only, a continued failure to perform assigned duties after receiving written notification of such failure from the Board of Directors, provided that such duties are those customarily performed by a person holding the position that such executive officer holds immediately prior to the Change in Control of a corporation of similar size and engaged in a similar line of business as us; or (vi) failure to cooperate in good faith with a governmental or internal investigation of us or our directors, officers or employees, if we have requested such cooperation.

        "Change in Control" means the occurrence of any of the following events:

•

any person is or becomes the beneficial owner, directly or indirectly, of our securities representing 50% or more of (i) the then outstanding shares of our common stock or (ii) the combined voting power of our then outstanding voting securities entitled to vote generally in the election of directors;



•

the following individuals cease for any reason to constitute a majority of the number of directors then serving on the Board of Directors ("Incumbent Board"): individuals who, as of the effective date of the applicable Management Retention Agreement, serve on the Board of Directors and any new director whose appointment or election by the Board of Directors or nomination for election by our stockholders was approved or recommended by a vote of at least two-thirds of the directors then still in office who either were directors as of such effective date or whose appointment, election or nomination for election was previously so approved or recommended;



•

a merger or consolidation of us or any direct or indirect subsidiary of ours is consummated with any other corporation, other than a merger or consolidation pursuant to which (i) our voting securities then outstanding immediately prior to such merger or consolidation will continue to represent more than 50% of the outstanding shares of common stock and the combined voting power of the outstanding voting securities entitled to vote generally in the election of directors, as the case may be, of us or such surviving entity or any parent thereof outstanding immediately after such merger or consolidation; (ii) no Person will become the beneficial owner, directly or indirectly, of our securities or the securities of such surviving entity or any parent thereof representing 50% or more of the outstanding shares of common stock or the combined voting power of the outstanding voting securities entitled to vote generally in the election of directors; and (iii) individuals who were members of the Incumbent Board will constitute at least a majority of the members of the board of directors of the corporation resulting from such merger or consolidation; or



•

our stockholders approve a plan of complete liquidation or dissolution or there is consummated an agreement for the sale or disposition of all or substantially all of our assets, other than a sale or disposition of all or substantially all of our assets to an entity, (i) more than 50% of the outstanding shares of common stock and the combined voting power of the outstanding voting securities entitled to vote generally in the election of directors, as the case may be, of which is owned by our stockholders in substantially the same proportions as their ownership immediately prior to such sale; (ii) in which no person is or becomes the beneficial owner, directly or indirectly, of our securities representing 50% or more of the outstanding shares of common stock resulting from such sale or disposition or the combined voting power of the outstanding voting securities entitled to vote generally in the election of directors; and (iii) in which individuals who were members of the Incumbent Board will constitute at least a majority of the members of the board of directors.

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        "Change in Control Period" means the period commencing three months prior to a Change in Control and ending twelve months after the Change in Control.

        "Good Reason" means, without the executive officer's consent, (i) a material reduction in his level of responsibility and/or scope of authority, (ii) a material reduction in base salary (other than a reduction generally applicable to other executive officers and in generally the same proportion), or (iii) relocation of his principal workplace by more than 35 miles. For purposes of this definition, the level of responsibility and/or scope of authority of Mr. Fernandez or Mr. Ball will be considered to be materially reduced if he no longer performs substantially the same functional role as that which he performed immediately prior to the occurrence of a Change of Control at an entity whose securities are publicly traded or his title changes, and a change in responsibility of any of Messrs. Holmes, Winter and Kinion will not be deemed to occur solely because he is part of a larger organization or solely because of a change in his title. In addition, upon any such voluntary termination for Good Reason, the executive officer must provide written notice of the existence of one or more of the above conditions within 60 days of its initial existence, we must be provided written or e-mailed notice with 30 days to remedy the condition and the resignation must be effective no later than 31 days following the provision of such written or e-mailed notice to us if such condition is not remedied.

Golden Parachute Compensation

        In accordance with Item 402(t) of Regulation S-K, the table below sets forth the compensation that is based on or otherwise relates to the Merger that will or may become payable to each of our named executive officers in connection with the Merger. Please see the previous portions of this section for further information regarding this compensation.

        The amounts indicated in the table below are estimates of the amounts that would be payable assuming, solely for purposes of this table, that the Merger is consummated on June 3, 2016, and that each named executive officer's employment is terminated by Marketo without Cause or by the named executive officer for Good Reason, in each case, on that date. Marketo's named executive officers will not receive pension, non-qualified deferred compensation, tax reimbursement or other benefits in connection with the Merger.

        Some of the amounts set forth in the table would be payable solely by virtue of the consummation of the Merger. In addition to the assumptions regarding the consummation date of the Merger and the termination of employment, these estimates are based on certain other assumptions that are described in the footnotes accompanying the table below. Accordingly, the ultimate values to be received by a named executive officer in connection with the Merger may differ from the amounts set forth below.

Golden Parachute Compensation

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Equity Interests of Marketo's Executive Officers and Non-Employee Directors

        The following table sets forth the number of shares of common stock and the number of shares of common stock underlying equity awards currently held by each of Marketo's executive officers and non-employee directors, in each case that either are currently vested or that are expected to vest in connection with the Merger, outstanding as of June 3, 2016. The table also sets forth the values of these shares and equity awards based on the Per Share Merger Consideration (minus the applicable exercise price for the Options). No additional shares of common stock or equity awards were granted to any executive officer or non-employee director in contemplation of the Merger.

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Equity Interests of Marketo's Executive Officers and Non-Employee Directors

Financing of the Merger

        We anticipate that the total amount of funds necessary to complete the Merger and the related transactions will be approximately $1.79 billion. This amount includes the funds needed to: (1) pay stockholders the amounts due under the Merger Agreement; (2) make payments in respect of our outstanding equity-based awards pursuant to the Merger Agreement; and (3) pay all fees and expenses payable by Parent and Merger Sub under the Merger Agreement.

        Although the obligation of Parent and Merger Sub to consummate the Merger is not subject to any financing condition, the Merger Agreement provides that, without Parent's agreement, the closing of the Merger will not occur earlier than the second business day after the expiration of the Marketing Period. For more information, please see the section of this proxy statement captioned, "Proposal 1: Adoption of the Merger Agreement—Marketing Period."

Equity Financing

        Pursuant to the Equity Commitment Letter, Vista Fund VI has agreed to provide Parent with an equity commitment of up to approximately $1.79 billion in cash, which will be available to fund the aggregate purchase price and the other payments contemplated by, and subject to the terms and conditions of, the Merger Agreement.

        The Equity Commitment Letter provides, among other things, that: (1) Marketo is an express third party beneficiary thereof in connection with Marketo's exercise of its rights related to specific performance under the Merger Agreement; and (2) Parent and Vista Fund VI will not oppose the granting of an injunction, specific performance or other equitable relief in connection with the exercise of such third party beneficiary rights. The Equity Commitment Letter may not be waived, amended or modified except by a written instrument signed by Parent, Vista Fund VI and Marketo.

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Limited Guaranty

        Pursuant to the Limited Guaranty, Vista Fund VI has agreed to guarantee the due, punctual and complete payment of all of the liabilities and obligations of Parent or Merger Sub under the Merger Agreement, including, but limited to: (1) the indemnification obligations of Parent and Merger Sub in connection with any costs, expenses or losses incurred or sustained by Marketo in connection with its cooperation with the arrangement of any potential debt financing; and (2) the documented and reasonable out-of-pocket costs and expenses incurred by Marketo in connection with the cooperation of Marketo with the potential arrangement of any potential debt financing. We refer to the obligations set forth in clauses (1) and (2) of the preceding sentence as the "Reimbursement Obligations," and to the obligations set forth in the preceding sentence as the "Guaranteed Obligations."

        The obligations of Vista Fund VI under the Limited Guaranty are subject to an aggregate cap equal to $116.3 million, plus the Reimbursement Obligations.

        Subject to specified exceptions, the Limited Guaranty will terminate upon the earliest of:

•

immediately following the Effective Time and the deposit of the Merger consideration with the designated payment agent;



•

the valid termination of the Merger Agreement by mutual written consent of Parent and Marketo;



•

the valid termination of the Merger Agreement by Marketo in certain circumstances in connection with a Superior Proposal;



•

the indefeasible payment by Vista Fund VI, Parent or Merger Sub of an amount of the Guaranteed Obligations equal to the aggregate cap; and



•

one year after the valid termination of the Merger Agreement in accordance with its terms, other than a termination in the scenarios described in the second and third bullet above (and, if Marketo has made a claim under the Guaranteed Obligations prior to such date, the Limited Guaranty will terminate on date that such claim is finally satisfied or otherwise resolved).