Separation Agreement between Detlev Biniszkiewicz, Ph.D. and the Registrant, dated September 27, 2017

Exhibit 10.16

September 27, 2017

Detlev M. Biniszkiewicz, PhD

Dear Detlev:

This sets forth the terms and conditions associated with the ending of your employment with Surface Oncology, Inc. (“Surface” or the “Company”). The Company’s Board of Directors (the “Board”) appreciates your contributions and would like to make this transition as smooth as possible. With that in mind and consistent with the terms of your March 7, 2015 Employment Agreement with the Company (the “Employment Agreement”), the Company shall provide you with the Termination Benefits set forth below provided you enter into, do not revoke and comply with the terms of this Separation Agreement (this “Agreement”). The Company is also electing to provide you with additional Termination Benefits not contemplated in the Employment Agreement in the form of additional vested equity, a revised mix of options for exercise, and a continued role with the Company as a director serving on the Board, all as set forth in this Agreement. With those understandings, September 15, 2017 shall be the “Date of Termination” and this document is the “Release” referenced in the Employment Agreement.

In connection with the ending of your employment and regardless of whether you sign this Agreement: (i) the Company shall pay your salary plus any accrued but unused vacation through the Date of Termination; the cash amount of such accrued but unused vacation is $11,569.23 (64 hours) and was paid to you as part of the Company’s September 15^th payroll; (ii) the Company shall reimburse you for any outstanding, reasonable business expenses that you incur on the Company’s behalf through the Date of Termination (provided the Company receives appropriate documentation in accordance with the Company’s reimbursement policies); (iii) your eligibility to participate in the Company’s health and dental coverage shall end on September 30, 2017 (provided you shall have an opportunity to continue your health, dental and vision insurance pursuant to the Consolidated Omnibus Budget Reconciliation Act of 1985 (“COBRA”) and subject to Section 4(b)); (iv) your eligibility to participate in any other employee benefit plans and programs of the Company shall cease on the Date of Termination in accordance with the terms and conditions of those plans; and (v) your outstanding equity awards shall vest until the Date of Termination and the terms of your equity awards shall be governed by the Company’s below referenced stock option plan and associated award agreements (without reference to this Agreement). A summary of your equity awards is attached as Exhibit A to this Agreement.

To the extent the ending of your relationship with the Company or any Company affiliate is not effectuated by your termination of employment, you hereby resign as President and Chief Executive Officer of the Company and all other affiliations that you have with the Company or any of its affiliates, such resignations effective on the Date of Termination. You agree to execute any reasonably requested resignation letters to confirm any such resignations. Notwithstanding the foregoing, you shall continue to serve as director of the Company on the terms set forth in letter agreement with the Company attached hereto as Exhibit B to this Agreement (the “Director Letter Agreement”).

Detlev M. Biniszkiewicz, Ph.D.

September 27, 2017

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The following plans and agreements continue to be in effect except to the extent specifically modified by this Agreement: the Employment Agreement, the Restrictive Covenant Agreement (defined below), the Restricted Stock Award Notice Under the Surface Oncology, Inc. 2014 Stock Option and Grant Plan and the associated Restricted Stock Agreement dated May 14, 2015 (the “Equity Award” (as also defined in the Employment Agreement)); the Incentive Stock Option Grant Notice and the attached Incentive Stock Option Agreement dated December 4, 2015 (the “2015 Option Grant”); the Incentive Stock Option Grant Notice and the attached Incentive Stock Option Agreement dated March 3, 2016 (the “2016 Option Grant”); the Incentive Stock Option Grant Notice and the attached Incentive Stock Option Agreement dated June 27, 2017 (the “2017 Option Grant”, and together with the 2015 Option Grant and the 2016 Option Grant, the “Option Grants”); the Promissory Note dated May 28, 2015 (the “Promissory Note”); and the Pledge Agreement dated May 28, 2015 (the “Pledge Agreement”). The Equity Award and the Option Grants are collectively referred to as the “Stock Grants.”

To receive Termination Benefits (as defined in the Employment Agreement), you must execute, not revoke and comply with this Agreement, including, without limitation, by complying with your ongoing obligations to the Company under this Agreement and the noncompetition, inventions or nondisclosure obligations that you owe to the Company, whether pursuant to applicable law or the Restrictive Covenant Agreement as defined below.

(a) continuation of your base salary for the nine (9) month period that immediately follows the Date of Termination in an amount equal to $282,000 (the “Salary Continuation Payments”);

(b) if elected, continuation of group health plan benefits to the extent authorized by and consistent with 29 U.S.C. § 1161 et seq. (commonly known as “COBRA”), with the cost of the regular premium for such benefits shared in the same relative proportion by the Company and you as in effect on the Date of Termination until the earlier of (i) the date that is nine (9) months after the Date of Termination; and (ii) the date you become eligible for health benefits through another employer or otherwise become ineligible for COBRA;

(c) the unvested portion of the Equity Award (but none of the Option Grants) shall accelerate and vest for an additional six months beyond the Date of Termination (amounting to an additional 96,270 shares of Common Stock of the Company (the “Common Stock”)); and

(d) a pro-rated bonus equal to $112,800, less deductions and withholdings (the “Prorated Bonus”).

Detlev M. Biniszkiewicz, Ph.D.

September 27, 2017

Page 3

The Salary Continuation Payments shall be made on the Company’s regular payroll dates commencing on the first payroll date after the Effective Date. In the event you miss a regular payroll period between the Date of Termination and first Salary Continuation Payment date, the first Salary Continuation Payment shall include a “catch up” payment. The Pro-rated Bonus shall be paid to you within five days of the Effective Date.

It is understood and agreed that, based on the Date of Termination and the 6-month acceleration of the Equity Award (but not the Option Grants) referenced above in Section 4(c), as of the Termination Date, awards with respect to an aggregate of 1,018,360 shares of Common Stock under the Option Grants (472,830 options) and the Equity Award (545,530 shares) are vested.

First, the Company is offering to accelerate an additional portion of the Stock Grants with respect to an aggregate of 139,482 shares, consisting of a mix of options for Common Stock or restricted stock under the Stock Grants, so that the total vested equity as of the Date of Termination under the Stock Grants shall be equal to an aggregate of 1,157,842 shares of Common Stock under the Option Grants and the Equity Award, all in.

Further, the Company has elected to compensate you with equity for your continued service to the Company as a Board director, with an option grant for 102,900 shares, vesting over a three year period on a monthly basis (so 2,858 options per month for the first 35 months, and 2,870 options for the 36^th month), such vesting to start on the Date of Termination and to continue on each month anniversary thereof for as long as you continue to maintain a Service Relationship (as defined in the Stock Grants) with the Company (such grant on those terms, the “Director Equity”). As described below, this equity grant will be achieved by restructuring the 2015 Option Grant.

To achieve that vested share position (i.e., 1,157,842 options and shares in total as of the Date of Termination) and the Director Equity (subject to further vesting), and to assist you in reducing cash payments to be made for those options and shares, notwithstanding anything herein to the contrary (provided you do not revoke this Agreement as provided below), the following is hereby agreed to by you and the Company:

Detlev M. Biniszkiewicz, Ph.D.

September 27, 2017

Page 4

The Stock Grants are hereby amended and restated to reflect the foregoing (subject to you not revoking this Agreement as provided below). You hereby confirm that you have no other right, title or interest in or to any equity or other securities of the Company (under the Employment Agreement or otherwise), except as expressly set forth in the Equity Award and the 2015 Option Grant, each as amended by this Agreement.

For clarity, any exercise period for the 2015 Option Grant, as amended by this Agreement, shall control the exercise period for options under that 2015 Option Grant (as so amended), and the Company makes not representation, warranty, covenant or other assertion as to whether any of the 2015 Option Grant (as so amended) qualifies, in whole or in part, as an “incentive stock option” as defined in Section 422 of the Internal Revenue Code of 1986, as amended from time to time.

In consideration of, among other things, the Termination Benefits, you irrevocably and unconditionally release and forever discharge the Company, all of its affiliated and related entities, its and their respective predecessors, successors and assigns, its and their respective employee benefit plans and the fiduciaries of such plans, and the current, future and former managers, members, partners, officers, directors, shareholders, employees, attorneys, accountants, and agents of each of the foregoing in their official and personal capacities (collectively referred to as the “Releasees”) generally from all claims, demands, debts, damages and liabilities of every name and nature, known or unknown (“Claims”) that, as of the date when you sign this Agreement, you have ever had, now claim to have or ever claimed to have had against any or all of the Releasees. This release includes, without limitation, the complete release of all Claims of or for: breach of express or implied contract; wrongful termination of employment whether in contract or tort; intentional, reckless, or negligent infliction of emotional distress; breach of any express or implied covenant of employment, including, without

Detlev M. Biniszkiewicz, Ph.D.

September 27, 2017

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limitation, the covenant of good faith and fair dealing, whether prospective or existing; deceit or misrepresentation; discrimination or retaliation under state, federal, or municipal law (including, without limitation, under Massachusetts General Law Ch. 151B, Title VII of the Civil Rights Act of 1964, the Age Discrimination in Employment Act (“ADEA”), the Americans with Disabilities Act of 1990, and the Family and Medical Leave Act); defamation or damage to reputation; reinstatement; punitive or emotional distress damages; equity compensation or other forms of compensation; and attorney’s fees and costs for wages, back or front pay, bonuses, severance pay, incentive compensation, commissions, stock, stock options, vacation pay or any other compensation or benefits, either under the Massachusetts Wage Act, M.G.L. c. 149, § 148-150C, or otherwise.

You understand that this general release of Claims extends to any and all claims through the date you sign this Agreement, including, without limitation, all claims related to equity of the Company and to your employment by the Company and your separation from that employment.

You acknowledge that you have returned to the Company all property of the Company, including, without limitation, keys and access cards, computer equipment, software licensed to the Company, files and any documents (including, without limitation, computerized data and any copies) containing information concerning the Company, its business or its business relationships (in the latter two cases, actual or prospective). You also commit that, upon request by the Company you shall delete and finally purge any duplicates of files or documents that may contain the Company’s information from any non-Company computer, Smartphone device or other device that remains your property after the Date of Termination, unless expressly authorized to keep duplicates of some of these materials. In any event, if you later discover that you continue to retain any such property, you shall return it to the Company immediately.

The Noncompetition and Nonsolicitation Confidentiality and Assignment Agreement which you entered into in connection with your employment (the “Restrictive Covenant Agreement”), appended hereto as Exhibit C to this Agreement shall remain in full force in effect in accordance with its terms and is hereby incorporated by reference into this Agreement.

You agree not to make any disparaging statements concerning the Company or any of its affiliates or their respective products or services, or any of the Company’s current, future or former managers, members, partners, officers, directors, shareholders, employees or agents. The obligations set forth herein shall not in any way affect your obligation to testify truthfully in any legal proceeding.

Detlev M. Biniszkiewicz, Ph.D.

September 27, 2017

Page 6

The Board shall work with you to develop an internal and external communication plan regarding your departure and the Company. If you are asked by any person or entity (whether or not affiliated with the Company) about the reasons for your departure from the Company, you shall respond in a way that is consistent with the communication and you shall not make negative statements about the Company, your employment or the reasons for your departure.

You agree to cooperate reasonably with the Company (including, without limitation, its outside counsel) in connection with the contemplation, prosecution and defense of all phases of existing, past and future litigation about which the Company believes you may have knowledge or information. You agree to make yourself available during and outside of regular business hours for such cooperation; provided that the Company shall not utilize this Section 11 to require you to make yourself available to an extent that would unreasonably interfere with your search for employment or any subsequent employment responsibilities that you may have. You agree to appear without the necessity of a subpoena to testify truthfully in any legal proceedings in which the Company calls you as a witness. In connection with fulfilling your obligations under this Section 11, your pre-approved, out of pocket and reasonable expenses shall be reimbursed by the Company.

You agree to keep the existence of the terms of this Agreement (“Agreement-Related Information”) strictly confidential and to not disclose Agreement-Related Information to anyone provided you may disclose Agreement-Related Information to your attorneys, tax advisors and your immediate family but only if such person first agrees to keep the Agreement-Related Information confidential.

If you apply to the Massachusetts Department of Unemployment Assistance for unemployment compensation benefits under state law, the Company shall not dispute your eligibility for such benefits. This shall not affect the Company’s obligation to respond truthfully to governmental agency requests for information related to unemployment compensation eligibility.

All payments set forth in this Agreement shall be subject to all applicable federal, state or local withholding or payroll taxes, and the Company may withhold from any amounts payable to you (including, without limitation, any amounts payable pursuant to this Agreement) in order to comply with such withholding obligations, including, without limitation, with respect to the Prorated Bonus based on the full amount thereof. Nothing herein shall be construed to mean that the Company shall compensate you for tax-related payments or liabilities.

Detlev M. Biniszkiewicz, Ph.D.

September 27, 2017

Page 7

This Agreement is a legally binding document, and your signature shall commit you to its terms. You acknowledge that you have it carefully read and fully understand all of the provisions of this Agreement, that the Company has advised you to consult with counsel prior to entering into this Agreement, and that you are voluntarily entering into this Agreement.

In signing this Agreement, you are not relying upon any promises or representations made by anyone at or on behalf of the Company except those promises and representations as provided in this Agreement.

If any portion or provision of this Agreement (including, without limitation, any portion or provision of any section of the Equity Award, 2015 Option Grant, the Director Letter or the Restrictive Covenant Agreement) shall to any extent be declared illegal or unenforceable by a court of competent jurisdiction, then the remainder of this Agreement, or the application of such portion or provision in circumstances other than those as to which it is so declared illegal or unenforceable, shall not be affected thereby, and each portion and provision of this Agreement shall be valid and enforceable to the fullest extent permitted by law.

No waiver of any provision of this Agreement shall be effective unless made in writing and signed by the waiving party. The failure of any party to require the performance of any term or obligation of this Agreement, or the waiver by any party of any breach of this Agreement, shall not prevent any subsequent enforcement of such term or obligation or be deemed a waiver of any subsequent breach. No amendment to any provision of this Agreement shall be effective unless made in writing and signed by all of the parties to this Agreement.

This Agreement shall be interpreted and enforced under the laws of the Commonwealth of Massachusetts, without regard to conflict of law principles. In the event of any dispute, this Agreement is intended by the parties to be construed as a whole, to be interpreted in accordance with its fair meaning, and not to be construed strictly for or against either you or the Company. The term “or” means “and/or”.

This Agreement along with the Restrictive Covenant Agreement, the Equity Award, the 2015 Option Grant, the Director Letter, the Promissory Note and the Pledge Agreement, constitutes the entire agreement between you and the Company. This Agreement and those agreement supersedes any previous agreements or understandings between you and the Company or any of their affiliates relating to the subject matter herein (including, without limitation, the Stock Grants except to the extent amended by this Agreement). You further acknowledge and agree that, expect as specifically set forth herein, you are not entitled to any other securities of, or payments or benefits from, the Company.

Detlev M. Biniszkiewicz, Ph.D.

September 27, 2017

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You acknowledge that you have been provided with the opportunity to consider this Agreement and the Director Letter for twenty-one (21) days before signing it. To accept this Agreement and the Director Letter, you must return a signed original of this Agreement and the Director Letter and the Check so that they are received by Lisa McGrath, Human Resources, or Company corporate counsel Goodwin Procter LLP, on or before the expiration of this twenty-one (21) day period. If you sign this Agreement and the Director Letter, and deliver the Check, within less than twenty-one (21) days of the date of its delivery to you, you acknowledge by signing this Agreement that such decision was entirely voluntary and that you had the opportunity to consider this Agreement and the Director Letter for the entire twenty-one (21) day period. You and the Company agree that any changes or modifications to this Agreement or the Director Letter shall not restart the twenty-one (21) day period. For a period of seven (7) days from the day of the execution of this Agreement and the Director Letter, and your delivery of the Check, you shall retain the right to revoke this Agreement and the Director Letter all together (and for clarity, not in part) by written notice that must be received by Ms. McGrath or corporate counsel before the end of such revocation period. This Agreement and the Director Letter shall become effective on the business day immediately following the expiration of the revocation period (the “Effective Date”), whereupon the Company will cash the Check, provided that you do not revoke this Agreement and the Director Letter during the revocation period. Upon any such revocation, this Agreement and the Director Letter shall be null and void (and for clarity the Stock Grants shall continue in full force and effect with reference to the terms of this Agreement, and the Check will be destroyed by the Company as provided above).

This Agreement may be executed in any number of counterparts, each of which when so executed and delivered shall be taken to be an original, but all of which together shall constitute one and the same document.

* * *

Detlev M. Biniszkiewicz, Ph.D.

September 27, 2017

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Please indicate your agreement to the terms of this Agreement by signing and returning the original of this letter to the undersigned within the time period set forth above.

Agreed to by:

SURFACE ONCOLOGY, INC.

Exhibit A

Exhibit B

Director Letter Agreement

September 27, 2017

Detlev M. Biniszkiewicz, PhD

Dear Detlev:

Surface Oncology, Inc. (the “Company”) is pleased to confirm its offer to you to continue to serve as a director on the Board of Directors (the “Board”) of the Company.

Your compensation for serving as a director of the Company will be at the rate of $25,000 per year, payable in four calendar quarterly installments of $6250, thirty (30) days in arrears after the end of each calendar quarter.

In addition to your cash compensation for serving as a director of the Company, options for common stock of the Company have been identified to vest with your continued service, pursuant to that certain agreement entitled “Separation Agreement” of around the same date hereof; those options are known as the “Director Equity” in that Separation Agreement. You should not expect to receive any other Company equity grants.

As you are aware, the Company is a Delaware corporation and, therefore, your rights and duties as a Board member are prescribed by Delaware law and the Company’s charter documents, as well as by the policies established by the Board from time to time.

It is understood that you will serve at the pleasure of the Company and that either you or the Company may terminate your directorship at any time and for any reason without prior notice and without additional compensation to you (and even if only some and not all of the Director Equity has vested).

You will be solely responsible for payment of all governmental charges and taxes arising from your service to the Company as a director.

This letter is in addition to, and not in lieu of, all other agreements you have with the Company, including, without limitation, the Separation Agreement and the other agreements referred to therein.

Please indicate your acceptance of this offer to continue to serve as a director of the Company by signing and dating the enclosed copy of this letter.

We look forward to your continued service on the Board.

Accepted and Agreed:

Date

Exhibit C

Restrictive Covenant Agreement

Attached.

SURFACE ONCOLOGY, INC.

Employee Non-Competition, Non-Solicitation, Confidentiality and Assignment Agreement

In consideration and as a condition of my employment or continued employment by Surface Oncology, Inc. (the “Company”), I agree as follows:

[End of Text]

I UNDERSTAND THAT THIS AGREEMENT AFFECTS IMPORTANT RIGHTS. BY SIGNING BELOW, I CERTIFY THAT I HAVE READ IT CAREFULLY AND AM SATISFIED THAT I UNDERSTAND IT COMPLETELY.

IN WITNESS WHEREOF, the undersigned has executed this agreement as a sealed instrument as of the date set forth below.

Type or print name:

Date:

EXHIBIT A

From:                                                              

Date:                                                               

SUBJECT: Prior Inventions

The following is a complete list of all inventions or improvements relevant to the subject matter of my employment by the Company that have been made or conceived or first reduced to practice by me alone or jointly with others prior to my engagement by the Company:

The following is a list of all patents and patent applications in which I have been named as an inventor: