Employment Offer Letter, dated as of May 17, 2018, between the Adicet Bio, Inc. and Stewart E. Abbot

Employment Offer

Salary. The Company agrees to pay you an annual salary of $365,000 (“Base Salary”), less all required deductions and withholdings, payable as earned in accordance with the Company’s customary payroll practices. 

Performance Bonus. You will be eligible to earn an annual performance bonus of up to 35% of your Base Salary, based on achievement of performance targets established by the Company. The amount of any such bonus will be determined in the sole discretion of the Company. You must be employed with the Company on the date such bonus is paid in order to be eligible for any bonus payment. Such bonus will be pro-rated for any partial year of employment.

Sign-On Bonus. The Company agrees to pay you a sign-on bonus of $275,000 in the aggregate, less all required deductions and withholdings (the “Sign-On Bonus”), which Sign-On Bonus shall be payable in two tranches and subject to the following terms:

Stock Options. Subject to approval of the Company’s Board of Directors (the “Board”), you will receive an option to purchase 683,800 shares of the Company’s common stock (the “Option”) pursuant to the Company’s 2015 Stock Incentive Plan. The per share exercise price of the Option will be equal to the per share fair market value of the Company’s common stock on the date of grant, as determined by the Board. The Option will be contingent upon you executing the Company’s standard stock option agreement. So long as you continue in service with the Company, the Option will vest and become exercisable with respect to 25% of the shares subject to the Option on the one-year anniversary of your start date, and with respect to the balance, in thirty-six (36) equal monthly installments upon your completion of each additional month of service thereafter.

Benefits. You will be eligible to participate in regular health insurance, vacation, and other employee benefit plans established by the Company for its employees from time to time on substantially the same terms as are made available to employees of the Company generally, provided you are eligible under (and subject to all provisions of) the plan documents governing those plans. You will be eligible to participate in retention, change in control or similar plans or programs (if any), as are made available to similarly situated executives of the Company, provided you are eligible under (and subject to all provisions of) the terms governing those plans or programs.

Commuting and Lodging Expenses. The Company will provide reimbursement for reasonable travel and lodging expense of up to $6,000 per month (for up to two years from your start date) related to your travel back and forth from San Diego, California to the San Francisco Bay Area to provide services under this Agreement, upon submission of proper vouchers and documentation in accordance with the Company’s expense reimbursement policy (“Commuting Expenses”). If you choose to relocate permanently (a “Permanent Relocation”), the Company will make a lump sum payment to you to cover Reasonable Moving Expenses (as defined below) of up to a maximum of $60,000 (the “Relocation Reimbursement”); provided, however, that if you are terminated for Cause (as defined below) or resign other than for Good Reason (as defined below) within

Other Expenses. The Company will reimburse you for all reasonable and necessary expenses incurred by you in connection with the Company’s business, in accordance with any applicable policy established by the Company from time to time.

Severance. Except in situations where your employment is terminated (1) by the Company for Cause (as defined below) or as a result of your death or Disability (as defined below), or (2) by you other than for Good Reason (as defined below), you will be eligible to receive the following severance benefits (collectively, the “Severance Benefits”):

An amount equal to six (6) months of your then-current Base Salary, less standard withholdings for tax and social security purposes, payable in six (6) equal monthly installments commencing within seventy (70) days following the date of termination of employment on the first payroll date following the date the Release (as defined below) becomes irrevocable (with the first payment including any installments that otherwise would have been paid between the date of termination and the date of such first installment); provided, however, that if the seventy (70) day period described above spans calendar years, the payments will commence in the second calendar year.

Subject to your timely election under COBRA, payment of your

If such termination of employment occurs within twelve months following a Liquidation (as defined in the Company’s Amended and Restated Certificate of Incorporation, as amended, modified or restated from time to time), the vesting of all unvested restricted stock, options or other equity incentive awards then held by you shall be accelerated such that all such restricted stock, options or other equity awards shall be deemed vested in full.

Eligibility. Your eligibility for the Severance Benefits is conditioned on you having first signed a release agreement in the form attached as Exhibit B (the “Release”) and such Release becoming effective pursuant to its terms no later than sixty (60) days following the date of termination of your employment (the “Release Deadline”). If the Release does not become effective and irrevocable by the Release Deadline, you forfeit any rights to the Severance Benefits described in this Section 4. ln no event will any Severance Benefits be paid under this Section 4 until the Release becomes effective and irrevocable and the Severance Benefits will commence or be provided once the Release becomes effective and irrevocable. You agree that the Company shall have a right of offset against all severance payments for amounts owed to the Company by you (unless the amounts owed are subject to a good faith dispute) to the fullest extent not prohibited by law. The Severance Benefits shall be in lieu of any other severance payments, severance benefits and severance protections to which you may be entitled under any severance or termination policy, plan, program, practice or arrangement of the Company and its affiliates. Except as specifically provided in this Section 4 or in another section of this letter agreement, or except as required by law, all benefits provided by the Company to you under this letter agreement or otherwise shall cease as of the date of termination of your employment. You shall not be entitled to any Severance Benefits if your employment is terminated (1) by the Company for Cause or as a result of your death or Disability, or (2) by you other than for Good Reason.

Certain Tax Provisions. It is intended that the terms of this offer of employment comply with Section 409A of the Code, and related Treasury regulations

Certain Definitions. For purposes of this letter agreement:

“Cause” shall mean: (A) performance of any act or failure to perform any act in bad faith and to the detriment of the Company or its affiliates, including, but not limited to, misappropriation of trade secrets, fraud or embezzlement; (B) material breach of any agreement with the Company or its affiliates; (C) commission of a crime involving dishonesty, breach of trust, or physical or emotional harm to any person, (D) your willful refusal to implement or follow a lawful policy or directive of the Company or its affiliates; or (E) your engagement in misfeasance or malfeasance demonstrated by a pattern of failure to perform job duties diligently and professionally.

“Disability” means disability as defined under the long-term disability policy of the Company regardless of whether you are covered by such policy. lf the Company does not have a long-term disability plan in place, “Disability” means that, in the sole opinion of the Company, you are unable to carry out the responsibilities and functions of the position you hold by reason of any medically determinable physical or mental impairment for a period of not less than ninety (90) consecutive days or more than one hundred and twenty days (120) in any twelve-month period.

“Good Reason” means any of the following events if (A) such event is affected without your consent, (B) you provide written notice to the Company that such event constitutes Good Reason within thirty (30) days of the occurrence thereof, (C) you provide the Company with a period of twenty (20) days to cure such event, and (D) the Company fails to cure such event within that period: (1) a change in your position with the Company which materially and substantially reduces your level of responsibility or duties; provided, however, that if the Company is being acquired and made part of a larger entity, a change in your position shall not constitute Good Reason if such change does not result in a material and substantial reduction in your level of responsibility or duties with respect to the Company’s business operations (whether as a subsidiary, business unit, division or otherwise of the acquirer) following such acquisition; (2) a material reduction in your Base Salary, except for reductions that are comparable to reductions generally applicable to similarly situated executives of the Company; or (3) a relocation of your principal place of employment by more than seventy five (75) miles from the Company’ s current headquarters.

Neither your execution and delivery of this letter agreement nor the performance of your duties and other obligations hereunder violate or will violate any statute or law or conflict with or constitute a default or breach of any covenant or obligation, including without limitation any non-competition restrictions, under any prior employment agreement, contract, or other instrument to which you are a party or by which you are bound (whether immediately, upon the giving of notice or lapse of time or both).

You have the full right, power and legal capacity to enter and deliver this letter agreement and to perform your duties and other obligations hereunder. This letter agreement constitutes the legal, valid and binding obligation of you enforceable against you in accordance with its terms. No approvals or consents of any persons or entities are required for you to execute and deliver this letter agreement or perform your duties and other obligations hereunder.

Executing the Company’s form of Employee Proprietary Information and Invention Assignment Agreement attached hereto as Exhibit A, which, among other things, prohibits unauthorized use or disclosure of the Company’s proprietary information;

Satisfying the requirements of the Immigration Control and Reform Act of 1986, which may be accomplished by showing your proof of right to work in the U.S. within three days of commencing employment (e.g., an original driver’s license and social security card, or a passport).

Satisfactorily completing a background check investigation.

Notwithstanding anything to the contrary, this offer may be withdrawn by the Company at any time by the Company’s Chief Executive Officer prior to the execution of this letter agreement by you.

/s/ Stewart E. Abbot