EXHIBIT 4.3

ERO COPPER CORP.
STOCK OPTION PLAN
EFFECTIVE MAY 7, 2020

Article 1
Introduction and Interpretation

The purpose of the Plan is to provide an incentive to the officers, employees, Consultants and other personnel of the Corporation or any of its subsidiaries to achieve the longer-term objectives of the Corporation; to give suitable recognition to the ability and industry of such persons who contribute materially to the success of the Corporation; and to attract to and retain in the employ of the Corporation or any of its subsidiaries, persons of experience and ability, by providing them with the opportunity to acquire an increased proprietary interest in the Corporation.

In this Plan, the following terms have the following meanings:

aggregate, more than 50% of all outstanding voting securities of the Corporation;

amendments to the articles of the Corporation, reorganization or otherwise, including any rights that form a part of the common share or substituted share;

The Plan shall be effective as of the Effective Date and Options may be granted immediately thereafter, subject to receipt of all regulatory approvals. The Committee shall review and confirm the terms of the Plan from time to time.

Article 2
Plan Administration

The Plan shall be administered by the Committee. Subject to the general purposes, terms and condition of the Plan, and to the direction of the Board, the Committee shall have the authority in its sole and absolute discretion to administer the Plan and to exercise all the powers and authorities either specifically granted to it under the Plan or necessary or advisable in the administration of the Plan, all acting reasonably and in good faith and subject to and not

inconsistent with the express provisions of this Plan. Where the Board has delegated a power or authority to the Committee, any reference to the Board in this Plan shall be deemed to be a reference to the Committee.

The powers and duties of the Committee include, without limitation, the following:

Without limiting the discretion conferred on the Committee pursuant to this Section 2.1, the Committee’s decision to approve the grant of an Option to an Eligible Person in any period shall not require the Committee to approve the grant of an Option to any Eligible Person in any other period; nor shall the Committee’s decision with respect to the size or terms and conditions of an Option grant in any period require it to approve the grant of Options of the same or similar size or with the same or similar terms and conditions to any Eligible Person in any other period. The Committee shall not be precluded from approving the grant of an Option to any Eligible Person solely because such Eligible Person may previously have been granted an Option under this Plan or any other similar compensation arrangement of the Corporation.

Options may be granted in respect of authorized and unissued Shares, provided that the aggregate number of Shares reserved for issuance under this Plan, subject to adjustment or increase of such number pursuant to the provisions of Section 7.2, and in combination with the aggregate number of Shares which may be issuable under any other Security Based Compensation Arrangement adopted by the Corporation, shall not exceed 8% of the number of issued and outstanding Shares (on a non-diluted basis) at the relevant time. Provided that such maximum number of Shares is not exceeded, following the exercise, expiration, cancellation or other termination of any Options under the Plan, a number of Shares equal to the number of Options or rights so exercised, expired, cancelled or terminated shall automatically become available for issuance in respect of Options that may subsequently be granted under the Plan. No fractional Shares may be purchased or issued under the Plan. In the event the number of Shares to be issued upon the exercise of an Option is a fraction, the Optionee will receive the next lowest whole number of Shares and will not receive any other form of compensation (cash or otherwise) for the fractional interest.

The Committee may, in its discretion, require as conditions to the grant or exercise of any Option, that the Optionee shall have:

Any Option granted under the Plan shall be subject to the requirement that, if at any time counsel to the Corporation shall determine that the listing, registration or qualification of the Shares subject to such Option upon any securities exchange or under any law or regulation of any jurisdiction, or the consent or approval of any securities exchange or any governmental or regulatory body, is necessary as a condition of, or in connection with, the grant or exercise of such Option or the issuance or purchase of Shares thereunder, such Option may not be accepted or exercised in whole or in part unless such listing, registration, qualification, consent or approval shall have been effected or obtained on conditions acceptable to the Board. Nothing herein shall be deemed to require the Corporation to apply for or to obtain such listing, registration, qualification, consent or approval. Shares shall not be issued pursuant to the exercise of an Option unless the exercise of such Option and the issuance and delivery of such Shares pursuant thereto shall comply with all relevant provisions of applicable securities law, including, without limitation, the U.S. Securities Act, the United States Securities Exchange Act of 1934, as amended, applicable U.S. state securities laws, the rules and regulations promulgated thereunder, and the requirements of any stock exchange or consolidated stock price reporting system on which prices for the Shares are quoted at any given time.

Article 3
Plan Participation

Options may be granted only to Eligible Persons as the Committee may determine, provided that no Eligible Person has any claim or right to be granted an Option. In determining the Eligible Persons to whom Options may be granted and the number of Options granted to any Eligible Person, the Committee may take into account such factors as it shall determine in its sole and absolute discretion.

Participation in the Plan by Eligible Persons is voluntary.

Article 4
Grant of Options

Subject to, and except as herein and as otherwise specifically provided for in this Plan, the number of Shares subject to each Option, the Exercise Price, the Expiry Date of each Option, the extent to which each Option vests and is exercisable from time to time during the term of the Option and other terms and conditions relating to each such Option shall be determined by the Committee; provided, however, that:

the Approval Date, or if the Approval Date occurred during a Blackout Period applicable to the relevant Optionee, then the Business Day immediately following the expiry of the Blackout Period applicable to the relevant Optionee; and

Each Option granted under the Plan shall be subject to the terms and conditions of the Plan and evidenced by a Notice of Grant of Options and such other terms and conditions as the Committee, in its discretion, shall establish. The form of Notice of Grant of Options is attached hereto as Schedule “A”.

The Exercise Price for Shares that are subject to any Option shall in no circumstances be lower than the Fair Market Value, calculated in accordance with the terms of the Plan at the date of grant of the Option.

Subject to Section 4.5, the number of Shares that may be issued to any individual Optionee under the Plan, in combination with the aggregate number of Shares which may be issuable under any other Security Based Compensation Arrangement adopted by the Corporation, within a one year period, shall not exceed 5% of the number of issued and outstanding Shares (on a non-diluted basis) at the date of grant of the Option (the “Individual Limit”).

Subject to regulatory approval and unless approved by the shareholders of the Corporation given by the affirmative vote of a majority of the votes cast at a meeting of shareholders of the Corporation, excluding the votes attached to Shares beneficially owned by Insiders to whom Options may be granted under the Plan, other than persons who are Insiders solely by virtue of being a director or senior officer of a subsidiary of the Corporation, and associates thereof:

Article 5
Exercise of Options

Subject to the provisions of the Plan, an Option may be exercised from time to time by delivery to the Plan Administrator or, if no Plan Administrator is appointed pursuant to the Plan, to the Corporation, a written notice of exercise specifying the number of Shares with respect to which the Options are being exercised and accompanied by payment in full, by way of cash, cheque or other form of payment acceptable to the Corporation, of (a) the Exercise Price of the Shares to be purchased and (b) an amount for any tax withholding or remittance obligations of the Optionee or the Corporation arising under Applicable Law (or by entering into some other arrangement acceptable to the Corporation). Certificates or other evidence of ownership for such Shares shall be issued and delivered to the Optionee within a reasonable time following the receipt of such notice and payment.

If, as and when any Shares have been duly purchased and paid for under the terms of an Option, and all conditions relating to the exercise of an Option have been fulfilled to the satisfaction of the Committee, such Shares shall be conclusively deemed allotted and issued as fully paid and non-assessable Shares at the price paid therefor.

Notwithstanding the above, the Corporation may implement (or cause to have implemented) such systems and procedures (including systems and procedures operated by the Plan Administrator) from time to time to facilitate the exercise of Options pursuant to this Plan and shall provide Optionees with all necessary details regarding such systems and procedures to facilitate the exercise of Options from time to time in accordance with their terms.

Notwithstanding any of the provisions of the Plan, any Notice of Grant of Options or any Option, the Corporation’s obligation to issue Shares to an Optionee pursuant to the exercise of any Option shall be subject to:

Subject to the provisions of the Plan and, upon prior approval of the Committee, once an Option has vested and become exercisable an Optionee may elect, in lieu of exercising such Option, to exercise such Option by surrendering such Option in exchange for the issuance of Shares equal to the number determined by dividing (a) the difference between the Fair Market Value (calculated as at the date of settlement) and the Exercise Price of such Option by (b) the Fair Market Value (calculated as at the date of settlement). An Option may be surrendered and disposed of pursuant to this Section 5.2 from time to time by delivery to the Plan Administrator or, if no Plan Administrator is appointed pursuant to the Plan, to the Corporation, at its head office or such other place as may be specified by the Plan Administrator or the Corporation, as the case may be, of (a) a written notice specifying that the Optionee has elected to effect such a net settlement of such Option and the number of Options to be exercised and (b) the payment of an amount for any tax withholding or remittance obligations of the Optionee or the Corporation arising under Applicable Law (or by entering into some other arrangement acceptable to the Corporation). The Corporation will not be required, upon the net settlement of any Options pursuant to this Section 5.2, to issue fractions of Shares or to distribute certificates which evidence fractional Shares. In the event the number of Shares to be issued upon the net settlement of an Option is a fraction, the Optionee will receive the next lowest whole number of Shares and will not receive any other form of compensation (cash or otherwise) for the fractional interest. Upon exercise of the foregoing, the number of Shares underlying the Options disposed of shall be deducted from the number of Shares reserved for issuance under the Plan.

No Option shall be exercised pursuant to this Article 5 during a Blackout Period.

Article 6
Termination of Employment

Subject to Sections 6.2, 6.3 and 6.4 hereof, or to any express resolution or other determination by the Board with respect to an Option or the terms of any Notice of Grant of Options, an Option, and all rights to purchase Shares pursuant thereto, shall expire and terminate immediately upon the Optionee ceasing to actively provide services to the Corporation in his or her capacity as a director, an officer, employee or Consultant of the Corporation, as the case may be.

Subject to any express resolution or other determination by the Committee with respect to an Option or the terms of any Notice of Grant of Options, if, before the Expiry Date of an Option,

the employment of the Optionee by the Corporation is terminated by either party for any reason whatsoever, other than death, Retirement, Long-Term Disability or termination for cause, such Option may, subject to the terms thereof (including the vesting provisions thereof) and any other terms of the Plan, be exercised by the Optionee, at any time within 60 days of the termination of such Optionee’s active employment or other service with the Corporation, but in any case prior to the Expiry Date of the Option in accordance with the terms thereof and only to the extent the Optionee was entitled to exercise the Option on the date of termination. For greater certainty, the termination of active employment shall be the last day an Eligible Person provides actual service to the Corporation pursuant to a written notice of termination and does not include any subsequent common law or contractual notice period.

If, before the Expiry Date of an Option in accordance with the terms thereof, the employment of the Optionee by the Corporation is terminated by reason of Retirement or as a result of Long-Term Disability, unless the Committee determines otherwise, all Options held by such Optionee which have vested in accordance with their terms may be exercised at any time within one year following the date of Retirement or termination of the Optionee as a result of a Long-Term Disability or prior to the Expiry Date, whichever is earlier. Options held by an Optionee whose employment has been terminated by reason of Retirement or as a result of Long-Term Disability shall continue to vest in accordance with their terms until the earlier of the date which is one year following the date of Retirement or termination of the Optionee as a result of Long-Term Disability and the Expiry Date.

If, before the Expiry Date of an Option in accordance with the terms thereof, the employment of the Optionee by the Corporation is terminated by reason of death, unless the Committee determines otherwise, all outstanding Options held by such Optionee shall become fully vested and may be exercised by the legal personal representative(s) of the estate of the Optionee (including such part, if any, thereof which, but for this Section 6.4, would not otherwise be able to be exercised) at any time within one year following the date of death of the Optionee or prior to the Expiry Date, whichever is earlier, and only to the extent the Option was entitled to exercise the Option on the date of death.

Subject to Section 6.4 in the case of the death of an Optionee, an Option granted to an Optionee, and the right to receive Shares pursuant thereto, is personal to such Optionee. Except as otherwise provided in this Plan, no assignment, sale, transfer, pledge or charge of an Option, whether voluntary, involuntary, by operation of law or otherwise, vests any interest or right in such Option whatsoever in any assignee or transferee and, immediately upon any assignment, sale, transfer, pledge or charge or attempt to assign, sell, transfer, pledge or charge, such Option shall terminate and be of no further force or effect.

A transfer of employment or services between the Corporation and a subsidiary or affiliate of the Corporation or between subsidiaries or affiliates of the Corporation shall not be considered an interruption or termination of the employment of an Optionee by the Corporation for any purpose of the Plan, and Options shall not be affected by any such transfer of employment or services.

Options shall not be affected by any change of employment of the Optionee or by the Optionee ceasing to be a director, an officer or Consultant of the Corporation where the Optionee at the same time continues to be an Eligible Person.

Article 7
Business Combinations and Certain Adjustments

Subject to Section 7.3, if, during the term of an outstanding Option, the Corporation completes any transaction which results in a Change of Control (referred to as a “Transaction”) all unvested Options shall vest, and if within 90 days or such other period of time that the Committee determines following the date of the completion of the Transaction an event or events that would constitute a “constructive dismissal” (as such term is defined pursuant to the common law) occur with respect to an Optionee, and within 90 days or such other period of time that the Committee determines following the date of such “constructive dismissal” such Optionee’s employment with the Corporation is terminated (whether at the discretion of the Optionee or otherwise):

Notwithstanding the foregoing, with respect to any performance-based Options granted under the Plan, vesting of an Option shall be dependent on achievement of the applicable performance criteria as of the date of the completion of the Transaction and/or be prorated to the date of the completion of the Transaction, as applicable.

Appropriate adjustments as regards Options granted or to be granted, in the number of Shares optioned and in the Exercise Price, shall be made by the Committee to give effect to adjustments in the number of Shares resulting from subdivisions, consolidations or reclassifications of the Shares, or other relevant changes in the Corporation. The appropriate adjustment in any particular circumstance shall be conclusively determined by the Committee in its sole discretion, subject to the direction of the Board, approval by the shareholders of the Corporation and to acceptance by the Exchange, respectively, if applicable.

Nothing in this Article 7 shall in any way affect or derogate from the ability of the Committee to accelerate the vesting of Options at any time in its sole discretion as provided for in Section 2.1(e).

If at any time after the grant of an Option to any Optionee and prior to the Expiry Date of such Option, the Shares shall be reclassified, reorganized or otherwise changed, otherwise than as specified in Section 7.2 or, subject to the provisions of Section 7.1 hereof, the Corporation shall consolidate, merge or amalgamate with or into another corporation (the corporation resulting or continuing from such consolidation, merger or amalgamation being herein called the “Successor Corporation”) the Optionee shall be entitled to receive upon the subsequent exercise of his, her or its Option in accordance with the terms hereof and shall accept in lieu of the number of Shares to which he, she or it was theretofore entitled upon such exercise but for the same aggregate consideration payable therefor, the aggregate number of shares of the appropriate class and/or other securities of the Corporation or the Successor Corporation (as the case may be) and/or other consideration from the Corporation or the Successor Corporation (as the case may be) that the Optionee would have been entitled to receive as a result of such reclassification, reorganization or other change or, subject to the provisions of Section 7.1 hereof, as a result of such consolidation, merger or amalgamation, if on the record date of such reclassification, reorganization or other change or the effective date of such consolidation, merger or amalgamation, as the case may be, he or she had been the registered holder of the number of Shares to which he or she was theretofore entitled upon such exercise.

Article 8
Amendment or Termination of the Plan

Subject to Sections 8.2, 8.3 and 8.4, the Board may, at any time and from time to time, without the approval of the holders of Shares or any other voting securities of the Corporation, suspend, discontinue or amend the Plan or an Option.

To the extent required by the Stock Exchange Rules, notwithstanding Section 8.1, the Board may not, without the approval of the holders of a majority of Shares and other voting securities of the Corporation present and voting in person or by proxy at a meeting of shareholders of the Corporation, amend the Plan or an Option to:

unless the change to the Plan or an Option results from the application of Article 7.

Unless an Optionee otherwise agrees, the Board may not suspend, discontinue or amend the Plan or amend any outstanding Option in a manner that would materially and adversely alter or impair any Option previously granted to an Optionee under the Plan, and any such suspension, discontinuance or amendment of the Plan or amendment to an Option shall apply only in respect of Options granted on or after the date of such suspension, discontinuance or amendment. No suspension, discontinuance or amendment of the Plan or amendment of an Option may contravene the requirements of the Exchange or any securities commission or regulatory body to which the Plan, the Option or the Corporation is now or may hereafter be subject.

The Board may not amend any provision of this Article 8 without the approval of the holders of a majority of Shares and other voting securities of the Corporation present and voting in person or by proxy at a meeting of shareholders of the Corporation.

Article 9
Accounts, Notices and Miscellaneous Provisions

The Plan Administrator (or if none is appointed, the Corporation) shall maintain records of the details of each Option granted to each Optionee under the Plan. Upon request therefor from an Optionee and at such other times as the Corporation shall determine, the Plan Administrator (or if none is appointed, the Corporation) shall furnish the Optionee with a statement setting forth details of his, her or its Options. Such statement shall be deemed to have been accepted by the Optionee as correct unless written notice to the contrary is given to the Plan Administrator (or if none is appointed, the Corporation) within 10 days after such statement is given to the Optionee.

Any payment, notice, statement, certificate or other instrument required or permitted to be given to an Optionee or any person claiming or deriving any rights through him shall be given by:

Any payment, notice, statement, certificate or instrument required or permitted to be given to the Plan Administrator or the Corporation, as the case may be, shall be given by mailing it, postage prepaid (provided that the postal service is then in operation) or delivering it to the Plan Administrator or the Corporation, as the case may be, at the following address:

Ero Copper Corp.

Suite 1050, 625 Howe Street

Vancouver, British Columbia V6C 2T6

Attention: Chief Financial Officer

Facsimile: (604) 398-3767

Any payment, notice, statement, certificate or instrument referred to in Sections 9.2 or 9.3, if delivered, shall be deemed to have been given or delivered, on the date on which it was delivered; if faxed, e-mailed or sent by other means of recorded electronic communication, shall be deemed to have been given or delivered, on the date of faxing, e-mailing or sending by other means of electronic communication, provided that such date is a Business Day and the communication is so faxed, e-mailed or sent before 4:30 p.m. on such date at the place of receipt, otherwise, such communication shall be deemed to have been given and delivered on the next following Business Day; or, if mailed (provided that the postal service is then in

operation), shall be deemed to have been given or delivered on the second Business Day following the date on which it was mailed.

The Plan (and any amendments thereto as required under Article 8) shall be subject to such future approvals of the shareholders of the Corporation and any stock exchange upon which the Shares trade from time to time as may be required under the terms of the Plan or such stock exchange from time to time. Any Options granted on terms requiring such approval shall be conditional upon such approval being given and no such Options may be exercised until such approval is given.

Notwithstanding anything else in this Plan, the Corporation may take such steps as are considered necessary or appropriate for the withholding of any taxes which the Corporation is required by any law or regulation of any governmental authority whatsoever to withhold in connection with any Share including, without limiting the generality of the foregoing, the withholding of all or any portion of any payment or the withholding of the issue of Shares to be issued under the Plan, until such time as the Eligible Person has paid the Corporation for any amount which the Corporation is required to withhold with respect to such taxes or other amounts. Without limitation to the foregoing, the Committee may adopt administrative rules under the Plan which provide for the sale of Shares (or a portion thereof) in the market upon the issuance of such Shares under the provisions of the Plan to satisfy withholding obligations under the Plan.

The terms of the Plan and Options granted hereunder to Eligible Persons subject to taxation under the United States Internal Revenue Code of 1986, as amended, shall be determined by taking into consideration Schedule B to the Plan setting forth special provisions applicable to such persons.

Any holder of an Option shall not possess any rights of ownership as a shareholder of the Corporation with respect to any of the Shares covered by such Option including, for greater certainty and without limitation, the right to receive dividends on such Shares and the right to exercise voting rights in respect of such Shares, until such holder shall have exercised such Option in accordance with the terms of the Plan and the issuance of the Shares by the Corporation.

Nothing in the Plan, any Notice of Grant of Options or any Option shall confer upon any Optionee any right to continue in the employ of the Corporation or any of its subsidiaries or affect in any way the right of the Corporation or any of its subsidiaries to terminate his or her employment at any time; nor shall anything in the Plan or any Option be deemed or construed to constitute an agreement, or any expression of intent, on the part of the Corporation or any of its subsidiaries to extend the employment of any Optionee beyond the time that he or she would normally be retired pursuant to the provisions of any present or future retirement plan of the Corporation or any of its subsidiaries, or any present or future retirement policy of the

Corporation or any of its subsidiaries, or beyond the time at which he or she would otherwise be retired pursuant to the provisions of any contract of employment of the Corporation or any of its subsidiaries.

All expenses in connection with the Plan shall be borne by the Corporation.

This Plan shall be governed by, construed and interpreted in accordance with the laws of the Province of British Columbia and the laws of Canada applicable therein.

If any provision of the Plan or part hereof is determined to be void or unenforceable in whole or in part, such determination shall not affect the validity or enforcement of any other provision or part thereof.

SCHEDULE “A”

NOTICE OF GRANT OF STOCK OPTIONS

DATE: [●]

The Corporation hereby notifies the Optionee as follows:

SCHEDULE “B”

Special Provisions Applicable to Optionees Subject to taxation under
the United States Internal Revenue Code

This special appendix sets forth special provisions of the Plan that apply to Optionees subject to taxation under the United States Internal Revenue Code of 1986, as amended.

For purposes of this Schedule “B”:

determined by the reasonable application of a reasonable valuation method in accordance with Treasury Regulation Section 1.409A-1(b)(5)(iv)(B).