Document:

EX-10.3

 Exhibit 10.3 

TSCAN THERAPEUTICS, INC. 

2021 EQUITY INCENTIVE PLAN 

(As Adopted on April 22, 2021) 

 TSCAN THERAPEUTICS, INC. 

2021 EQUITY INCENTIVE PLAN 

ARTICLE 1.    INTRODUCTION. 

The Board adopted the Plan to become effective immediately, although no Awards may be granted prior to the IPO Date. The purpose of the Plan is
to promote the long-term success of the Company and the creation of stockholder value by (a) encouraging Service Providers to focus on critical long-range corporate objectives, (b) encouraging the attraction and retention of Service
Providers with exceptional qualifications and (c) linking Service Providers directly to stockholder interests through increased stock ownership. The Plan seeks to achieve this purpose by providing for Awards in the form of Options (which may be
ISOs or NSOs), SARs, Restricted Shares and Restricted Stock Units. Capitalized terms used in this Plan are defined in Article 14. 
 ARTICLE
2.    ADMINISTRATION. 
 2.1    General. The Plan may be administered by the
Board or one or more Committees to which the Board (or an authorized Board committee) has delegated authority. If administration is delegated to a Committee, the Committee shall have the powers theretofore possessed by the Board, including, to the
extent permitted by applicable law, the power to delegate to a subcommittee any of the administrative powers the Committee is authorized to exercise (and references in this Plan to either the Board or the Administrator shall hereafter also encompass
the Committee or subcommittee, as applicable). The Board may abolish the Committee’s delegation at any time and the Board shall at all times also retain the authority it has delegated to the Committee. The Administrator shall comply with rules
and regulations applicable to it, including under the rules of any exchange on which the Common Shares are traded, and shall have the authority and be responsible for such functions as have been assigned to it. 

2.2    Section 16. To the extent desirable to qualify transactions hereunder as exempt under Exchange Act
Rule 16b-3, the transactions contemplated hereunder will be approved by the entire Board or a Committee of two or more “non-employee directors” within the
meaning of Exchange Act Rule 16b-3. 
 2.3    Powers of
Administrator. Subject to the terms of the Plan, and in the case of a Committee, subject to the specific duties delegated to the Committee, the Administrator shall have the authority to (a) select the Service Providers who are to receive
Awards under the Plan, (b) determine the type, number, vesting requirements and other features and conditions of such Awards, (c) interpret the Plan and Awards granted under the Plan, (d) determine whether, when and to what extent an
Award has become vested and/or exercisable and whether any performance-based vesting conditions have been satisfied, (e) make, amend and rescind rules relating to the Plan and Awards granted under the Plan, including rules relating to sub-plans established for the purposes of satisfying applicable foreign laws or for qualifying for favorable tax treatment under applicable foreign laws, (f) impose such restrictions, conditions or limitations
as it determines appropriate as to the timing and manner of any resales by a Participant of any Common Shares issued pursuant to an Award, including restrictions under an insider trading policy and restrictions as to the use of a specified brokerage
firm for such resales, 

 
and (g) make all other decisions relating to the operation of the Plan and Awards granted under the Plan. In addition, with regard to the terms and conditions of Awards granted to Service
Providers outside of the United States, the Administrator may vary from the provisions of the Plan (other than any requiring stockholder approval pursuant to Section 13.3) to the extent it determines it necessary and appropriate to do so. 

2.4    Effect of Administrator’s Decisions. The Administrator’s decisions, determinations and
interpretations shall be final and binding on all interested parties. 
 2.5    Governing Law. The Plan
shall be governed by, and construed in accordance with, the laws of the State of Delaware (except its choice-of-law provisions). 

ARTICLE 3.    SHARES AVAILABLE FOR GRANTS. 

3.1    Basic Limitation. Common Shares issued pursuant to the Plan may be authorized but unissued shares or
treasury shares. The aggregate number of Common Shares issued under the Plan shall not exceed the sum of (a) 26,880,000 Common Shares, (b) any Common Shares subject to awards granted under the Predecessor Plan that are outstanding on the
IPO Date that subsequently are forfeited, expire or lapse unexercised or unsettled and Common Shares issued pursuant to awards granted under the Predecessor Plan that are outstanding on the IPO Date and that are subsequently forfeited to or
reacquired by the Company, (c) the number of Common Shares reserved under the Predecessor Plan that are not issued or subject to outstanding awards under the Predecessor Plan on the IPO Date and (d) the additional Common Shares described
in Articles 3.2 and 3.3. The Company shall reserve and keep available such number of Common Shares as will be sufficient to satisfy the requirements of the Plan. The numerical limitations in this Article 3.1 shall be subject to
adjustment pursuant to Article 9. 
 3.2    Annual Increase in Shares. On the first day of each fiscal year of the Company during the term of the Plan, commencing in 2022 and ending in (and including) 2031, the aggregate number of Common Shares that may be issued under the Plan shall
automatically increase by a number equal to the lesser of (a) 5% of the total number of Common Shares actually issued and outstanding on the last day of the preceding fiscal year or (b) a number of Common Shares determined by the Board.

 3.3    Shares Returned to Reserve. To the extent that Options, SARs, Restricted Stock Units or other
Awards are forfeited, cancelled or expire for any reason before being exercised or settled in full, the Common Shares subject to such Awards shall again become available for issuance under the Plan. If SARs are exercised or Restricted Stock Units
are settled, then only the number of Common Shares (if any) actually issued to the Participant upon exercise of such SARs or settlement of such Restricted Stock Units, as applicable, shall reduce the number of Common Shares available under
Article 3.1 and the balance shall again become available for issuance under the Plan. If Restricted Shares or Common Shares issued upon the exercise of Options are reacquired by the Company pursuant to a forfeiture provision, repurchase right
or for any other reason, then such Common Shares shall again become available for issuance under the Plan. Common Shares applied to pay the Exercise Price of Options or to satisfy tax withholding obligations related to any Award shall again become
available for issuance under the Plan. To the extent that an Award is settled in cash rather than Common Shares, the cash settlement shall not reduce the number of Shares available for issuance under the Plan. 

 3.4    Awards Not Reducing Share Reserve. To the extent
permitted under applicable exchange listing standards, any dividend equivalents paid or credited under the Plan with respect to Restricted Stock Units shall not be applied against the number of Common Shares that may be issued under the Plan,
whether or not such dividend equivalents are converted into Restricted Stock Units. In addition, Common Shares subject to Substitute Awards granted by the Company shall not reduce the number of Common Shares that may be issued under Article 3.1, nor
shall shares subject to Substitute Awards again be available for Awards under the Plan in the event of any forfeiture, expiration or cash settlement of such Substitute Awards. 

3.5    Code Section 422 and Other Limits. Subject to adjustment in accordance with
Article 9: 
 (a)    No more than 26,880,000 Common Shares may be issued under the Plan upon the exercise of ISOs. 

(b)    The aggregate grant date fair value of Awards granted to an Outside Director during any one fiscal year of the
Company, together with the value of any cash compensation paid to the Outside Director during such fiscal year, may not exceed $750,000 (on a per-Director basis); provided however that the limitation that will
apply in the fiscal year in which the Outside Director is initially appointed or elected to the Board shall instead be $1,500,000. For purposes of this limitation, the grant date fair value of an Award shall be determined in accordance with the
assumptions that the Company uses to estimate the value of share-based payments for financial reporting purposes. For the sake of clarity, neither Awards granted, nor compensation paid, to an individual for his or her service as an Employee or
Consultant, but not as an Outside Director, shall count towards this limitation. 
 ARTICLE 4.    ELIGIBILITY. 

4.1    Incentive Stock Options. Only Employees who are common-law
employees of the Company, a Parent or a Subsidiary shall be eligible for the grant of ISOs. In addition, an Employee who owns more than 10% of the total combined voting power of all classes of outstanding stock of the Company or any of its Parents
or Subsidiaries shall not be eligible for the grant of an ISO unless the additional requirements set forth in Code Section 422(c)(5) are satisfied. 

4.2    Other Awards. Awards other than ISOs may be granted to both Employees and other Service
Providers. 
 ARTICLE 5.    OPTIONS. 

5.1    Stock Option Agreement. Each grant of an Option under the Plan shall be evidenced by a Stock Option
Agreement between the Optionee and the Company. Such Option shall be subject to all applicable terms of the Plan and may be subject to any other terms that are not inconsistent with the Plan. The Stock Option Agreement shall specify whether the
Option is intended to be an ISO or an NSO. The provisions of the various Stock Option Agreements entered into under the Plan need not be identical. 

5.2    Number of Shares. Each Stock Option Agreement shall specify the number of Common Shares subject to
the Option, which number shall adjust in accordance with Article 9. 

 5.3    Exercise Price. Each Stock Option Agreement shall
specify the Exercise Price, which shall not be less than 100% of the Fair Market Value of a Common Share on the date of grant. The preceding sentence shall not apply to an Option that is a Substitute Award granted in a manner that would satisfy the
requirements of Code Section 409A and, if applicable, Code Section 424(a). 
 5.4    Exercisability
and Term. Each Stock Option Agreement shall specify the date or event when all or any installment of the Option is to become vested and/or exercisable. The vesting and exercisability conditions applicable to the Option may include service-based
conditions, performance-based conditions, such other conditions as the Administrator may determine, or any combination of such conditions. The Stock Option Agreement shall also specify the term of the Option; provided that, except to the extent
necessary to comply with applicable foreign law, the term of an Option shall in no event exceed 10 years from the date of grant. A Stock Option Agreement may provide for accelerated vesting and/or exercisability upon certain specified events
and may provide for expiration prior to the end of its term in the event of the termination of the Optionee’s service. 

5.5    Death of Optionee. After an Optionee’s death, any vested and exercisable Options held by
such Optionee may be exercised by his or her beneficiary or beneficiaries. Each Optionee may designate one or more beneficiaries for this purpose by filing the prescribed form with the Company. A beneficiary designation may be changed by filing the
prescribed form with the Company at any time before the Optionee’s death. If no beneficiary was designated or if no designated beneficiary survives the Optionee, then any vested and exercisable Options held by the Optionee may be exercised by
his or her estate. 
 5.6    Modification or Assumption of Options. Within the limitations of the Plan,
the Administrator may modify, extend or assume outstanding options. The foregoing notwithstanding, no modification of an Option shall, without the consent of the Optionee, materially impair his or her rights or obligations under such Option.
Notwithstanding anything in this Plan to the contrary, and except for the adjustments provided in Article 9, neither the Administrator nor any other person may (a) decrease the exercise price for any outstanding Option after the date of grant,
(b) cancel or allow an Optionee to surrender an outstanding Option to the Company in exchange for cash or as consideration for the grant of a new Option with a lower exercise price or the grant of another type of Award the effect of which is to
reduce the exercise price of any outstanding Option, or (c) take any other action with respect to an Option that would be treated as a repricing under the rules and regulations of the Nasdaq Stock Market (or such other principal U.S. national
securities exchange on which the Common Shares are traded). 
 5.7    Buyout Provisions. Except to the
extent prohibited by Article 5.6, the Administrator may at any time (a) offer to buy out for a payment in cash or cash equivalents an Option previously granted or (b) authorize an Optionee to elect to cash out an Option previously granted,
in either case at such time and based upon such terms and conditions as the Administrator shall establish. 

5.8    Payment for Option Shares. The entire Exercise Price of Common Shares issued upon exercise of Options
shall be payable in cash or cash equivalents at the time when such Common Shares are purchased. In addition, the Administrator may, in its sole discretion 

 
and to the extent permitted by applicable law, accept payment of all or a portion of the Exercise Price through any one or a combination of the following forms or methods: 

(a)    Subject to any conditions or limitations established by the Administrator, by surrendering, or attesting to the
ownership of, Common Shares that are already owned by the Optionee with a value on the date of surrender equal to the aggregate exercise price of the Common Shares as to which such Option will be exercised; 

(b)    By delivering (on a form prescribed by the Company) an irrevocable direction to a securities broker approved by the
Company to sell all or part of the Common Shares being purchased under the Plan and to deliver all or part of the sales proceeds to the Company; 

(c)    Subject to such conditions and requirements as the Administrator may impose from time to time, through a net
exercise procedure; or 
 (d)    Through any other form or method consistent with applicable laws, regulations and
rules. 
 ARTICLE 6.    STOCK APPRECIATION RIGHTS. 

6.1    SAR Agreement. Each grant of a SAR under the Plan shall be evidenced by a SAR Agreement between the
Optionee and the Company. Such SAR shall be subject to all applicable terms of the Plan and may be subject to any other terms that are not inconsistent with the Plan. The provisions of the various SAR Agreements entered into under the Plan need not
be identical. 
 6.2    Number of Shares. Each SAR Agreement shall specify the number of Common Shares to
which the SAR pertains, which number shall adjust in accordance with Article 9. 
 6.3    Exercise
Price. Each SAR Agreement shall specify the Exercise Price, which shall in no event be less than 100% of the Fair Market Value of a Common Share on the date of grant. The preceding sentence shall not apply to a SAR that is a Substitute Award
granted in a manner that would satisfy the requirements of Code Section 409A. 
 6.4    Exercisability
and Term. Each SAR Agreement shall specify the date when all or any installment of the SAR is to become vested and exercisable. The vesting and exercisability conditions applicable to the SAR may include service-based conditions,
performance-based conditions, such other conditions as the Administrator may determine, or any combination thereof. The SAR Agreement shall also specify the term of the SAR; provided that except to the extent necessary to comply with applicable
foreign law, the term of a SAR shall not exceed 10 years from the date of grant. A SAR Agreement may provide for accelerated vesting and exercisability upon certain specified events and may provide for expiration prior to the end of its term in the
event of the termination of the Optionee’s service. 
 6.5    Exercise of SARs. Upon exercise of a
SAR, the Optionee (or any person having the right to exercise the SAR after his or her death) shall receive from the Company (a) Common Shares, (b) cash or (c) a combination of Common Shares and cash, as the Administrator shall
determine. The amount of cash and/or the Fair Market Value of Common Shares received upon exercise of SARs shall, in the aggregate, not exceed the amount by which the Fair Market Value 

 
(on the date of surrender) of the Common Shares subject to the SARs exceeds the Exercise Price. If, on the date when a SAR expires, the Exercise Price is less than the Fair Market Value on such
date but any portion of such SAR has not been exercised or surrendered, then such SAR shall automatically be deemed to be exercised as of such date with respect to such portion. A SAR Agreement may also provide for an automatic exercise of the SAR
on an earlier date. 
 6.6    Death of Optionee. After an Optionee’s death, any vested and
exercisable SARs held by such Optionee may be exercised by his or her beneficiary or beneficiaries. Each Optionee may designate one or more beneficiaries for this purpose by filing the prescribed form with the Company. A beneficiary designation may
be changed by filing the prescribed form with the Company at any time before the Optionee’s death. If no beneficiary was designated or if no designated beneficiary survives the Optionee, then any vested and exercisable SARs held by the Optionee
at the time of his or her death may be exercised by his or her estate. 
 6.7    Modification or Assumption of
SARs. Within the limitations of the Plan, the Administrator may modify, extend or assume outstanding SARs. The foregoing notwithstanding, no modification of a SAR shall, without the consent of the Optionee, materially impair his or her rights or
obligations under such SAR. Notwithstanding anything in this Plan to the contrary, and except for the adjustments provided in Article 9, neither the Administrator nor any other person may (a) decrease the exercise price for any outstanding SAR
after the date of grant, (b) cancel or allow an Optionee to surrender an outstanding SAR to the Company in exchange for cash or as consideration for the grant of a new SAR with a lower exercise price or the grant of another type of Award the
effect of which is to reduce the exercise price of any outstanding SAR, or (c) take any other action with respect to a SAR that would be treated as a repricing under the rules and regulations of the Nasdaq Stock Market (or such other principal
U.S. national securities exchange on which the Common Shares are traded). 
 ARTICLE 7.    RESTRICTED SHARES. 

7.1    Restricted Stock Agreement. Each grant of Restricted Shares under the Plan shall be evidenced by a
Restricted Stock Agreement between the recipient and the Company. Such Restricted Shares shall be subject to all applicable terms of the Plan and may be subject to any other terms that are not inconsistent with the Plan. The provisions of the
various Restricted Stock Agreements entered into under the Plan need not be identical. 
 7.2    Payment for
Awards. Restricted Shares may be sold or awarded under the Plan for such consideration as the Administrator may determine, including (without limitation) cash, cash equivalents, property, cancellation of other equity awards, promissory notes,
past services and future services, and such other methods of payment as are permitted by applicable law. 

7.3    Vesting Conditions. Each Award of Restricted Shares may or may not be subject to vesting and/or other
conditions as the Administrator may determine. Vesting shall occur, in full or in installments, upon satisfaction of the conditions specified in the Restricted Stock Agreement. A Restricted Stock Agreement may provide for accelerated vesting upon
certain specified events. 
 7.4    Voting and Dividend Rights. The holders of Restricted Shares awarded
under the Plan shall have the same voting, dividend and other rights as the Company’s other stockholders, unless the Administrator otherwise provides. A Restricted Stock Agreement, 

 
however, may require that any cash dividends paid on Restricted Shares (a) be accumulated and paid when such Restricted Shares vest, or (b) be invested in additional Restricted Shares.
Such additional Restricted Shares shall be subject to the same conditions and restrictions as the shares subject to the Award with respect to which the dividends were paid. In addition, if any dividends or other distributions are paid in Common
Shares, such Common Shares shall be subject to the same restrictions on transferability and forfeitability as the Restricted Shares with respect to which they were paid. 

7.5    Modification or Assumption of Restricted Shares. Within the limitations of the Plan, the
Administrator may modify or assume outstanding Restricted Shares or may accept the cancellation of outstanding restricted shares (whether granted by the Company or by another issuer) in return for the grant of new Restricted Shares for the same or a
different number of shares or in return for the grant of a different type of Award. The foregoing notwithstanding, no modification of Restricted Shares shall, without the consent of the Participant, materially impair his or her rights or obligations
under such Restricted Shares. 
 ARTICLE 8.    RESTRICTED STOCK UNITS. 

8.1    Restricted Stock Unit Agreement. Each grant of Restricted Stock Units under the Plan shall be
evidenced by a Restricted Stock Unit Agreement between the recipient and the Company. Such Restricted Stock Units shall be subject to all applicable terms of the Plan and may be subject to any other terms that are not inconsistent with the Plan. The
provisions of the various Restricted Stock Unit Agreements entered into under the Plan need not be identical. 

8.2    Payment for Awards. To the extent that an Award is granted in the form of Restricted Stock Units, no
cash consideration shall be required of the Award recipients. 
 8.3    Vesting Conditions. Each Award of
Restricted Stock Units may or may not be subject to vesting, as determined by the Administrator. Vesting shall occur, in full or in installments, upon satisfaction of the conditions specified in the Restricted Stock Unit Agreement. Vesting
conditions may include service-based conditions, performance-based conditions, such other conditions as the Administrator may determine, or any combination thereof. A Restricted Stock Unit Agreement may provide for accelerated vesting upon certain
specified events. 
 8.4    Voting and Dividend Rights. The holders of Restricted Stock Units shall have
no voting rights. Prior to settlement or forfeiture, Restricted Stock Units awarded under the Plan may, at the Administrator’s discretion, provide for a right to dividend equivalents. Such right entitles the holder to be credited with an amount
equal to all cash dividends paid on one Common Share while the Restricted Stock Unit is outstanding. Dividend equivalents may be converted into additional Restricted Stock Units. Settlement of dividend equivalents may be made in the form of cash, in
the form of Common Shares, or in a combination of both. Prior to distribution, any dividend equivalents shall be subject to the same conditions and restrictions as the Restricted Stock Units to which they attach. 

8.5    Form and Time of Settlement of Restricted Stock Units. Settlement of vested Restricted
Stock Units may be made in the form of (a) cash, (b) Common Shares or (c) any combination of both, as determined by the Administrator. The actual number of Restricted Stock Units eligible for settlement may be larger or smaller than
the number included in the original 

 
Award, based on predetermined performance factors. Methods of converting Restricted Stock Units into cash may include (without limitation) a method based on the average value of Common Shares
over a series of trading days. Vested Restricted Stock Units shall be settled in such manner and at such time(s) as specified in the Restricted Stock Unit Agreement. Until an Award of Restricted Stock Units is settled, the number of such Restricted
Stock Units shall be subject to adjustment pursuant to Article 9. 
 8.6    Death of Recipient. Any
Restricted Stock Units that become payable after the recipient’s death shall be distributed to the recipient’s beneficiary or beneficiaries. Each recipient of Restricted Stock Units under the Plan may designate one or more beneficiaries
for this purpose by filing the prescribed form with the Company. A beneficiary designation may be changed by filing the prescribed form with the Company at any time before the Award recipient’s death. If no beneficiary was designated or if no
designated beneficiary survives the Award recipient, then any Restricted Stock Units that become payable after the recipient’s death shall be distributed to the recipient’s estate. 

8.7    Modification or Assumption of Restricted Stock Units. Within the limitations of the
Plan, the Administrator may modify or assume outstanding restricted stock units or may accept the cancellation of outstanding restricted stock units (whether granted by the Company or by another issuer) in return for the grant of new Restricted
Stock Units for the same or a different number of shares or in return for the grant of a different type of Award. The foregoing notwithstanding, no modification of a Restricted Stock Unit shall, without the consent of the Participant, materially
impair his or her rights or obligations under such Restricted Stock Unit. 

8.8    Creditors’ Rights. A holder of Restricted Stock Units shall have no rights other
than those of a general creditor of the Company. Restricted Stock Units represent an unfunded and unsecured obligation of the Company, subject to the terms and conditions of the applicable Restricted Stock Unit Agreement. 

ARTICLE 9.    ADJUSTMENTS; DISSOLUTIONS AND LIQUIDATIONS; CORPORATE TRANSACTIONS. 

9.1    Adjustments. In the event of a subdivision of the outstanding Common Shares, a declaration of a
dividend payable in Common Shares, a combination or consolidation of the outstanding Common Shares (by reclassification or otherwise) into a lesser number of Common Shares or any other increase or decrease in the number of issued Common Shares
effected without receipt of consideration by the Company, proportionate adjustments shall be made to the following: 

(a)    The number and kind of shares available for issuance under Article 3, including the numerical share limits in
Articles 3.1 and 3.5; 
 (b)    The number and kind of shares covered by each outstanding Option, SAR, and Restricted
Stock Unit; and/or 
 (c)    The Exercise Price applicable to each outstanding Option and SAR, and the repurchase price,
if any, applicable to Restricted Shares. 
 In the event of a declaration of an extraordinary dividend payable in a form other than Common Shares in an
amount that has a material effect on the price of Common Shares, a recapitalization, 

 
a spin-off or a similar occurrence, the Administrator shall make such adjustments as it, in its sole discretion, deems appropriate to the foregoing. Any
adjustment in the number of shares subject to an Award under this Article 9.1 shall be rounded down to the nearest whole share, although the Administrator in its sole discretion may make a cash payment in lieu of a fractional share. Except as
provided in this Article 9, a Participant shall have no rights by reason of any issuance by the Company of stock of any class or securities convertible into stock of any class, any subdivision or consolidation of shares of stock of any class,
the payment of any stock dividend or any other increase or decrease in the number of shares of stock of any class. 

9.2    Dissolution or Liquidation. To the extent not previously exercised or settled, Options, SARs and
Restricted Stock Units shall terminate immediately prior to the dissolution or liquidation of the Company. 

9.3    Corporate Transactions. In the event that the Company is a party to a merger, consolidation, or a
Change in Control (other than one described in Article 14.6(d)), all Common Shares acquired under the Plan and all Awards outstanding on the effective date of the transaction shall be treated in the manner described in the definitive transaction
agreement (or, in the event the transaction does not entail a definitive agreement to which the Company is party, in the manner determined by the Administrator, with such determination having final and binding effect on all parties), which agreement
or determination need not treat all Awards (or portions thereof) in an identical manner. Unless an Award Agreement provides otherwise, the treatment specified in the transaction agreement or by the Administrator may include (without limitation) one
or more of the following with respect to each outstanding Award: 
 (a)    The continuation of such
outstanding Award by the Company (if the Company is the surviving entity); 
 (b)    The assumption of
such outstanding Award by the surviving entity or its parent, provided that the assumption of an Option or a SAR shall comply with applicable tax requirements; 

(c)    The substitution by the surviving entity or its parent of an equivalent award for such outstanding
Award (including, but not limited to, an award to acquire the same consideration paid to the holders of Common Shares in the transaction), provided that the substitution of an Option or a SAR shall comply with applicable tax requirements; 

(d)    In the case of an Option or SAR, the cancellation of such Award without payment of any
consideration. An Optionee shall be able to exercise his or her outstanding Option or SAR, to the extent such Option or SAR is then vested or become vested as of the effective time of the transaction, during a period of not less than five full
business days preceding the closing date of the transaction, unless (i) a shorter period is required to permit a timely closing of the transaction and (ii) such shorter period still offers the Optionees a reasonable opportunity to exercise
such Option or SAR. Any exercise of such Option or SAR during such period may be contingent on the closing of the transaction; 

(e)    The cancellation of such Award and a payment to the Participant with respect to each share subject
to the portion of the Award that is vested or 

 
becomes vested as of the effective time of the transaction equal to the excess of (A) the value, as determined by the Administrator in its absolute discretion, of the property
(including cash) received by the holder of a Common Share as a result of the transaction, over (if applicable) (B) the per-share Exercise Price of such Award (such excess, if any, the “Spread”). Such payment shall be made
in the form of cash, cash equivalents, or securities of the surviving entity or its parent having a value equal to the Spread. In addition, any escrow, holdback, earn-out or similar provisions in the
transaction agreement may apply to such payment to the same extent and in the same manner as such provisions apply to the holders of Common Shares. If the Spread applicable to an Award (whether or not vested) is zero or a negative number,
then the Award may be cancelled without making a payment to the Participant. In the event that an Award is subject to Code Section 409A, the payment described in this clause (e) shall be made on the settlement date specified in the
applicable Award Agreement, provided that settlement may be accelerated in accordance with Treasury Regulation Section 1.409A-3(j)(4); or 

(f)    The assignment of any reacquisition or repurchase rights held by the Company in respect of an Award
of Restricted Shares to the surviving entity or its parent, with corresponding proportionate adjustments made to the price per share to be paid upon exercise of any such reacquisition or repurchase rights. 

Unless an Award Agreement provides otherwise, each outstanding Award held by a Participant who remains a Service Provider as of the effective time of a
merger, consolidation or Change in Control (other than one described in Article 14.6(d)) (a “Current Participant”) shall become fully vested and, if applicable, exercisable immediately prior to the effective time of the transaction
and, in the case of an Award subject to performance-based vesting conditions, such performance-based vesting conditions shall be deemed achieved at 100% of target levels. However, the prior sentence shall not apply, and an outstanding Award
shall not become vested and, if applicable, exercisable, if and to the extent the Award is continued, assumed or substituted as provided for in clauses (a), (b) or (c) above. In addition, the prior two sentences shall not apply to an
Award held by a Participant who is not a Current Participant unless an Award Agreement provides otherwise or unless the Company and the acquirer agree otherwise. 

For avoidance of doubt, the Administrator shall have the discretion, exercisable either at the time an Award is granted or at any time while the Award remains
outstanding, to provide for the acceleration of vesting upon the occurrence of a Change in Control, whether or not the Award is to be assumed or replaced in the transaction, or in connection with a termination of the Participant’s service
following a transaction. 
 Any action taken under this Article 9.3 shall either preserve an Award’s status as exempt from Code Section 409A or
comply with Code Section 409A. 
 ARTICLE 10.    OTHER AWARDS. 

Subject in all events to the limitations under Article 3 above as to the number of Common Shares available for issuance under this Plan, the
Company may grant other forms of Awards not specifically described herein and may grant awards under other plans or programs, where such awards are settled in the form of Common Shares issued under this Plan. Such Common Shares shall be treated for
all purposes under the Plan like Common Shares issued in settlement of Restricted Stock Units and shall, when issued, reduce the number of Common Shares available under Article 3. 

 ARTICLE 11.    LIMITATION ON RIGHTS. 

11.1    Retention Rights. Neither the Plan nor any Award granted under the Plan shall be deemed to give any
individual a right to remain a Service Provider. The Company and its Parents, Subsidiaries and Affiliates reserve the right to terminate the Service of any Service Provider at any time, with or without cause, subject to applicable laws, the
Company’s certificate of incorporation and by-laws and a written employment agreement (if any). 

11.2    Stockholders’ Rights. Except as set forth in Article 7.4 or 8.4 above, a
Participant shall have no dividend rights, voting rights or other rights as a stockholder with respect to any Common Shares covered by his or her Award prior to the time when a stock certificate for such Common Shares is issued or, if applicable,
the time when he or she becomes entitled to receive such Common Shares by filing any required notice of exercise and paying any required Exercise Price. No adjustment shall be made for cash dividends or other rights for which the record date is
prior to such time, except as expressly provided in the Plan. 
 11.3    Regulatory Requirements. Any
other provision of the Plan notwithstanding, the obligation of the Company to issue Common Shares under the Plan shall be subject to all applicable laws, rules and regulations and such approval by any regulatory body as may be required. The Company
reserves the right to restrict, in whole or in part, the delivery of Common Shares pursuant to any Award prior to the satisfaction of all legal requirements relating to the issuance of such Common Shares, to their registration, qualification or
listing or to an exemption from registration, qualification or listing. The inability of the Company to obtain authority from any regulatory body having jurisdiction, which authority is deemed necessary by the Company’s counsel to be necessary
to the lawful issuance and sale of any Common Shares hereunder, will relieve the Company of any liability in respect of the failure to issue or sell such Common Shares as to which such requisite authority will not have been obtained. 

11.4    Transferability of Awards. The Administrator may, in its sole discretion, permit
transfer of an Award in a manner consistent with applicable law. Unless otherwise determined by the Administrator, Awards shall be transferable by a Participant only by (a) beneficiary designation, (b) a will or (c) the laws of
descent and distribution; provided that, in any event, an ISO may only be transferred by will or by the laws of descent and distribution and may be exercised during the lifetime of the Optionee only by the Optionee or by the Optionee’s guardian
or legal representative. 
 11.5    Recoupment Policy. All Awards granted under the Plan, all
amounts paid under the Plan and all Common Shares issued under the Plan shall be subject to recoupment, clawback or recovery by the Company in accordance with applicable law and with Company policy (whenever adopted) regarding same, whether or not
such policy is intended to satisfy the requirements of the Dodd-Frank Wall Street Reform and Consumer Protection Act, the Sarbanes-Oxley Act, or other applicable law, as well as any implementing regulations and/or listing standards thereunder. 

11.6    Other Conditions and Restrictions on Common Shares. Any Common Shares issued under the Plan shall be
subject to such forfeiture conditions, rights of repurchase, rights of 

 
first refusal, other transfer restrictions and such other terms and conditions as the Administrator may determine. Such conditions and restrictions shall be set forth in the applicable Award
Agreement and shall apply in addition to any restrictions that may apply to holders of Common Shares generally. In addition, Common Shares issued under the Plan shall be subject to such conditions and restrictions imposed either by applicable law or
by Company policy, as adopted from time to time, designed to ensure compliance with applicable law or laws with which the Company determines in its sole discretion to comply including in order to maintain any statutory, regulatory or tax advantage.

 ARTICLE 12.    TAXES. 

12.1    General. It is a condition to each Award under the Plan that a Participant or his or her successor
shall make arrangements satisfactory to the Company for the satisfaction of any federal, state, local or foreign withholding tax obligations that arise in connection with any Award granted under the Plan. The Company shall not be required to issue
any Common Shares or make any cash payment under the Plan unless such obligations are satisfied. 

12.2    Share Withholding. To the extent that applicable law subjects a Participant to tax withholding
obligations, the Administrator may permit such Participant to satisfy all or part of such obligations by having the Company withhold all or a portion of any Common Shares that otherwise would be issued to him or her or by surrendering all or a
portion of any Common Shares that he or she previously acquired. Such Common Shares shall be valued on the date when they are withheld or surrendered. Any payment of taxes by assigning Common Shares to the Company may be subject to restrictions
including any restrictions required by SEC, accounting or other rules. 
 12.3    Section 409A Matters.
Except as otherwise expressly set forth in an Award Agreement, it is intended that Awards granted under the Plan either be exempt from, or comply with, the requirements of Code Section 409A. To the extent an Award is subject to Code
Section 409A (a “409A Award”), the terms of the Plan, the Award and any written agreement governing the Award shall be interpreted to comply with the requirements of Code Section 409A so that the Award is not subject to
additional tax or interest under Code Section 409A, unless the Administrator expressly provides otherwise. A 409A Award shall be subject to such additional rules and requirements as specified by the Administrator from time to time in order for
it to comply with the requirements of Code Section 409A. In this regard, if any amount under a 409A Award is payable upon a “separation from service” to an individual who is considered a “specified employee” (as each term is
defined under Code Section 409A), then no such payment shall be made prior to the date that is the earlier of (i) six months and one day after the Participant’s separation from service or (ii) the Participant’s death, but
only to the extent such delay is necessary to prevent such payment from being subject to Code Section 409A(a)(1). 

12.4    Limitation on Liability. Neither the Company nor any person serving as Administrator shall have any
liability to a Participant in the event an Award held by the Participant fails to achieve its intended characterization under applicable tax law. 

ARTICLE 13.    FUTURE OF THE PLAN. 

13.1    Term of the Plan. The Plan, as set forth herein, shall become effective on the date of its adoption
by the Board, subject to approval of the Company’s stockholders under Article 13.3 below. The Plan shall terminate automatically 10 years after the date when the Board adopted the Plan. 

 13.2    Amendment or Termination. The Board may, at any
time and for any reason, amend or terminate the Plan. No Awards shall be granted under the Plan after the termination thereof. The termination of the Plan, or any amendment thereof, shall not affect any Award previously granted under the Plan. 

13.3    Stockholder Approval. To the extent required by applicable law, the Plan will be subject to the
approval of the Company’s stockholders within 12 months of its adoption date. An amendment of the Plan shall be subject to the approval of the Company’s stockholders only to the extent required by applicable laws, regulations or rules.

 ARTICLE 14.    DEFINITIONS. 

14.1    “Administrator” means the Board or any Committee administering the Plan in accordance with Article
2. 
 14.2    “Affiliate” means any entity other than a Subsidiary, if the Company and/or one or more
Subsidiaries own not less than 50% of such entity. 
 14.3    “Award” means any award granted under the
Plan, including as an Option, a SAR, a Restricted Share award, a Restricted Stock Unit award or another form of equity-based compensation award. 

14.4    “Award Agreement” means a Stock Option Agreement, a SAR Agreement, a Restricted Stock Agreement,
a Restricted Stock Unit Agreement or such other agreement evidencing an Award granted under the Plan. 

14.5    “Board” means the Company’s Board of Directors, as constituted from time to time and, where
the context so requires, reference to the “Board” may refer to a Committee to whom the Board has delegated authority to administer any aspect of this Plan. 

14.6    “Change in Control” means: 

(a)    Any “person” (as such term is used in Sections 13(d) and 14(d) of the Exchange Act) becomes the
“beneficial owner” (as defined in Rule 13d-3 of the Exchange Act), directly or indirectly, of securities of the Company representing more than fifty percent (50%) of the total voting power
represented by the Company’s then-outstanding voting securities; 
 (b)    The consummation of the sale or
disposition by the Company of all or substantially all of the Company’s assets; 
 (c)    The consummation of a
merger or consolidation of the Company with or into any other entity, other than a merger or consolidation which would result in the voting securities of the Company outstanding immediately prior thereto continuing to represent (either by remaining
outstanding or by being converted into voting securities of the surviving entity or its parent) more than fifty percent (50%) of the total voting power represented by the voting securities of the Company or such surviving entity or its parent
outstanding immediately after such merger or consolidation; or 

 (d)    Individuals who are members of the Board (the “Incumbent
Board”) cease for any reason to constitute at least a majority of the members of the Board over a period of 12 months; provided, however, that if the appointment or election (or nomination for election) of any new Board member was approved
or recommended by a majority vote of the members of the Incumbent Board then still in office, such new member shall, for purposes of this Plan, be considered as a member of the Incumbent Board. 

A transaction shall not constitute a Change in Control if its sole purpose is to change the state of the Company’s incorporation or to create a holding
company that will be owned in substantially the same proportions by the persons who held the Company’s securities immediately before such transaction. In addition, if a Change in Control constitutes a payment event with respect to any
Award which provides for a deferral of compensation and is subject to Code Section 409A, then notwithstanding anything to the contrary in the Plan or applicable Award Agreement the transaction with respect to such Award must also constitute a
“change in control event” as defined in Treasury Regulation Section 1.409A-3(i)(5) to the extent required by Code Section 409A. 

14.7    “Code” means the Internal Revenue Code of 1986, as amended. 

14.8    “Committee” means a committee of one or more members of the Board, or of other individuals
satisfying applicable laws, appointed by the Board to administer the Plan. 
 14.9    “Common Share”
means one share of the Company’s common stock. 
 14.10    “Company” means TScan Therapeutics,
Inc., a Delaware corporation. 
 14.11    “Consultant” means a consultant or adviser who provides
bona fide services to the Company, a Parent, a Subsidiary or an Affiliate as an independent contractor and who qualifies as a consultant or advisor under Instruction A.1.(a)(1) of Form S-8 under the
Securities Act. 
 14.12    “Employee” means a common-law
employee of the Company, a Parent, a Subsidiary or an Affiliate. 
 14.13    “Exchange Act” means the
Securities Exchange Act of 1934, as amended. 
 14.14    “Exercise Price,” in the case of an Option,
means the amount for which one Common Share may be purchased upon exercise of such Option, as specified in the applicable Stock Option Agreement. “Exercise Price,” in the case of a SAR, means an amount, as specified in the applicable SAR
Agreement, which is subtracted from the Fair Market Value of one Common Share in determining the amount payable upon exercise of such SAR. 

14.15    “Fair Market Value” means the closing price of a Common Share on any established stock exchange
or a national market system on the applicable date or, if the applicable date is not a trading day, on the last trading day prior to the applicable date, as reported in a source that the Administrator deems reliable. If Common Shares are not traded
on an established stock exchange or a national market system, the Fair Market Value shall be determined by the Administrator in good faith on such basis as it deems appropriate. The Administrator’s determination shall be conclusive and binding
on all persons. Notwithstanding the foregoing, the determination of the Fair Market Value in all cases shall be in accordance with the requirements set forth under Section 409A of the Code to the extent necessary for an Award to comply with, or
be exempt from, Section 409A of the Code. 

 14.16    “IPO Date” means the effective date of the
registration statement filed by the Company with the Securities and Exchange Commission for its initial offering of the Common Shares to the public. 

14.17    “ISO” means an incentive stock option described in Code Section 422(b). 

14.18    “NSO” means a stock option not described in Code Sections 422 or 423. 

14.19    “Option” means an ISO or NSO granted under the Plan and entitling the holder to purchase Common
Shares. 
 14.20    “Optionee” means an individual or estate holding an Option or SAR. 

14.21    “Outside Director” means a member of the Board who is not an Employee. 

14.22    “Parent” means any corporation (other than the Company) in an unbroken chain of corporations
ending with the Company, if each of the corporations other than the Company owns stock possessing 50% or more of the total combined voting power of all classes of stock in one of the other corporations in such chain. A corporation that attains the
status of a Parent on a date after the adoption of the Plan shall be considered a Parent commencing as of such date. 

14.23    “Participant” means an individual or estate holding an Award. 

14.24    “Plan” means this TScan Therapeutics, Inc. 2021 Equity Incentive Plan, as amended from time to
time. 
 14.25    “Predecessor Plan” means the Company’s 2018 Stock Plan, as amended. 

14.26    “Restricted Share” means a Common Share awarded under the Plan. 

14.27    “Restricted Stock Agreement” means the agreement consistent with the terms of the Plan between
the Company and the recipient of a Restricted Share that contains the terms, conditions and restrictions pertaining to such Restricted Share. 

14.28    “Restricted Stock Unit” means a bookkeeping entry representing the equivalent of one Common
Share, as awarded under the Plan. 
 14.29    “Restricted Stock Unit Agreement” means the agreement
consistent with the terms of the Plan between the Company and the recipient of a Restricted Stock Unit that contains the terms, conditions and restrictions pertaining to such Restricted Stock Unit. 

14.30    “SAR” means a stock appreciation right granted under the Plan. 

14.31    “SAR Agreement” means the agreement consistent with the terms of the Plan between the Company
and an Optionee that contains the terms, conditions and restrictions pertaining to his or her SAR. 

 14.32    “Securities Act” means the Securities Act of
1933, as amended. 
 14.33    “Service Provider” means any individual who is an Employee, Outside
Director or Consultant, including any prospective Employee, Outside Director or Consultant who has accepted an offer of employment or service and will be an Employee, Outside Director or Consultant after the commencement of their service. 

14.34    “Stock Option Agreement” means the agreement consistent with the terms of the Plan between the
Company and an Optionee that contains the terms, conditions and restrictions pertaining to his or her Option. 

14.35    “Subsidiary” means any corporation (other than the Company) in an unbroken chain of corporations
beginning with the Company, if each of the corporations other than the last corporation in the unbroken chain owns stock possessing 50% or more of the total combined voting power of all classes of stock in one of the other corporations in such
chain. A corporation that attains the status of a Subsidiary on a date after the adoption of the Plan shall be considered a Subsidiary commencing as of such date 

14.36    “Substitute Awards” means Awards or Common Shares issued by the Company in assumption of, or
substitution or exchange for, awards previously granted, or the right or obligation to make future awards, in each case by a corporation acquired by the Company or any Affiliate or with which the Company or any Affiliate combines to the extent
permitted by the applicable exchange listing standards. 

 TSCAN THERAPEUTICS, INC. 

2021 EQUITY INCENTIVE PLAN 

NOTICE OF STOCK OPTION GRANT 

You have been granted the following option to purchase shares of the common stock of TScan Therapeutics, Inc. (the “Company”): 

 

			
	 Name of Optionee:
	  	 «Name»

		
	 Total Number of Shares:
	  	 «TotalShares»

		
	 Type of Option:
	  	 «ISO» Incentive Stock Option

		
		  	 «NSO» Nonstatutory Stock Option

		
	 Exercise Price per Share:
	  	 $«PricePerShare»

		
	 Date of Grant:
	  	 «DateGrant»

		
	 Vesting Commencement Date:
	  	 «VestDay»

		
	 Vesting Schedule:
	  	This option shall vest and become exercisable with respect to the first «CliffPercent» of the shares subject to this option when you complete «CliffPeriod» months of continuous service as an [Employee or
Consultant][Outside Director] (“Service”) after the Vesting Commencement Date. This option shall vest and become exercisable with respect to an additional «IncrementalPercent» of the shares subject to this option when you
complete each additional month of continuous Service thereafter.
		
	Expiration Date:	  	«ExpDate». This option expires earlier if your Service terminates earlier, as described in the Stock Option Agreement, and may terminate earlier in connection with certain corporate transactions as described in
Article 9 of the Plan.

 You and the Company agree that this option is granted under and governed by the terms and conditions of the
Company’s 2021 Equity Incentive Plan (the “Plan”) and the Stock Option Agreement, both of which are attached to, and made a part of, this document. Capitalized terms not otherwise defined herein shall have the meanings assigned to
such terms in the Plan. 
 The Company may, in its sole discretion, decide to deliver any documents related to options awarded under the Plan, future
options that may be awarded under the Plan and all other documents that the Company is required to deliver to security holders (including annual reports and proxy statements) by email or other electronic means (including by posting them on a website
maintained by the Company or a third party under contract with the Company). You hereby consent to receive such documents by electronic delivery and agree to participate in the Plan through any on-line or
electronic system established and maintained by the Company or another third party designated by the Company. You acknowledge that you may incur costs in connection with any such delivery by means of electronic transmission, including the cost of
accessing the Internet and printing fees, and that an interruption of Internet access may interfere with your ability to access the documents. 
 You
further agree to comply with the Company’s Insider Trading Policy when selling shares of the Company’s common stock. 

 TSCAN THERAPEUTICS, INC. 

2021 EQUITY INCENTIVE PLAN 

STOCK OPTION AGREEMENT 

 

			
	Grant of Option	  	 Subject to all of the terms and conditions set forth in the Notice of Stock Option Grant (the “Grant Notice”), this Stock Option
Agreement (the “Agreement”) and the Plan, the Company has granted you an option to purchase up to the total number of shares specified in the Grant Notice at the exercise price indicated in the Grant Notice.

 
 All capitalized terms used in this Agreement shall have the meanings assigned to them in
this Agreement, the Grant Notice or the Plan.

		
	Tax Treatment	  	This option is intended to be an incentive stock option under Section 422 of the Code or a nonstatutory stock option, as provided in the Grant Notice. However, even if this option is designated as an incentive stock option in
the Grant Notice, it shall be deemed to be a nonstatutory stock option to the extent it does not qualify as an incentive stock option under federal tax law, including under the $100,000 annual limitation under Section 422(d) of the
Code.
		
	Vesting	  	 This option vests and becomes exercisable in accordance with the vesting schedule set forth in the Grant Notice.

 
 In no event will this option vest or become exercisable for additional shares after your
Service has terminated for any reason unless expressly provided in a written agreement between you and the Company.

		
	Term of Option	  	This option expires in any event at the close of business at Company headquarters on the day before the 10th anniversary of the Date of Grant, as shown in the Grant Notice. (This option will expire earlier if your Service terminates
earlier, as described below, and this option may be terminated earlier as provided in Article 9 of the Plan.)
		
	Termination of Service	  	If your Service terminates for any reason, this option will expire to the extent it is unvested as of your termination date and does not vest as a result of your termination of Service. The Company determines whether and when your
Service terminates for all purposes of this option.
		
	Regular Termination	  	If your Service terminates for any reason except death or total and permanent disability, then this option, to the extent vested as of your termination date, will expire at the close of business at Company headquarters on the date
three months after your termination date.

			
	Death	  	If your Service terminates as a result of your death, then this option, to the extent vested as of the date of your death, will expire at the close of business at Company headquarters on the date twelve months after the date of
death.
		
	Disability	  	 If your Service terminates because of your total and permanent disability, then this option, to the extent vested as of your termination
date, will expire at the close of business at Company headquarters on the date six months after your termination date.
  

For all purposes under this Agreement, “total and permanent disability” means that you are unable to engage in any substantial gainful activity by
reason of any medically determinable physical or mental impairment which can be expected to result in death or which has lasted, or can be expected to last, for a continuous period of not less than one year.

		
	Leaves of Absence and Part-Time Work	  	 For purposes of this option, your Service does not terminate when you go on a military leave, a sick leave or another bona fide leave
of absence, if the leave was approved by the Company in writing, and if continued crediting of Service is required by applicable law, the Company’s leave of absence policy or the terms of your leave. However, your Service terminates when the
approved leave ends, unless you immediately return to active work.
  
 If you go on a
leave of absence, or if you commence working on a part-time basis, the Company may adjust the vesting schedule in accordance with the Company’s leave of absence policy or the terms of your leave or so that the rate of vesting is commensurate
with your reduced work schedule, as applicable.

		
	Restrictions on Exercise	  	The Company will not permit you to exercise this option if the issuance of shares at that time would violate any law or regulation.
		
	Notice of Exercise	  	 When you wish to exercise this option, you must notify the Company by filing the proper “Notice of Exercise” form at the address
given on the form or, if the Company has designated a third party to administer the Plan, you must notify such third party in the manner such third party requires. Your notice must specify how many shares you wish to purchase. The notice will be
effective when the Company receives it.
  
 However, if you wish to exercise this option
by executing a same-day sale (as described below), you must follow the instructions of the Company and the broker who will execute the sale.

 
 If someone else wants to exercise this option after your death, that person must prove
to the Company’s satisfaction that he or she is entitled to do so.
  
 You may only
exercise your option for whole shares.

			
	Form of Payment	  	 When you submit your notice of exercise, you must make arrangements for the payment of the option exercise price for the shares that you are
purchasing. To the extent permitted by applicable law, payment may be made in one (or a combination of two or more) of the following forms:

  

•   By delivering to the Company your personal check, a cashier’s check or a money order,
or arranging for a wire transfer.
  

•   By giving to a securities broker approved by the Company irrevocable directions to sell all
or part of your option shares and to deliver to the Company, from the sale proceeds, an amount sufficient to pay the option exercise price and any Tax-Related Items (as defined below). (The balance of the sale
proceeds, if any, will be delivered to you.) The directions must be given in accordance with the instructions of the Company and the broker. This exercise method is sometimes called a “same-day
sale.”
  
 The Company may permit other forms of payment in its discretion to the
extent permitted by the Plan.

		
	 Withholding Taxes
	  	 Regardless of any action the Company (or, if applicable, the Parent, Subsidiary or Affiliate employing or retaining you (the
“Employer”)) takes with respect to any or all income tax, social insurance, payroll tax, payment on account or other tax-related items related to the participation in the Plan and legally applicable
to you (“Tax-Related Items”), you acknowledge that the ultimate liability for all Tax-Related Items is and remains your responsibility and may exceed the
amount actually withheld by the Company and/or the Employer. You further acknowledge that the Company and the Employer (1) make no representations or undertakings regarding the treatment of any
Tax-Related Items in connection with any aspect of the options, including, but not limited to, the grant, vesting or exercise of the option, the issuance of shares upon exercise of the option, the subsequent
sale of shares acquired pursuant to such exercise and the receipt of any dividends and/or any dividend equivalents; and (2) do not commit to and are under no obligation to structure the terms of the option or any aspect of the option to reduce
or eliminate your liability for Tax-Related Items or achieve any particular tax result. Further, if you are subject to tax in more than one jurisdiction, you acknowledge that the Company and/or the Employer
may be required to withhold or account for Tax-Related Items in more than one jurisdiction.
  

You will not be allowed to exercise this option unless you make arrangements acceptable to the Company and/or the Employer to pay any Tax-Related Items that the Company and/or the Employer determine must be withheld. These arrangements include payment in cash or via the same-day sale procedure described
above. With the Company’s consent, these arrangements may also include (a) withholding shares of Company stock that otherwise would be issued to you when you exercise this option with a value equal to withholding taxes,
(b) surrendering

			
		  	shares that you previously acquired with a value equal to the withholding taxes, or (c) withholding cash from other compensation. The value of withheld or surrendered shares, determined as of the date when taxes otherwise would
have been withheld in cash, will be applied to the Tax-Related Items.
		
	Restrictions on Resale	  	You agree not to sell any option shares at a time when applicable laws, Company policies or an agreement between the Company and its underwriters prohibit a sale. This restriction will apply as long as your Service continues and for
such period of time after the termination of your Service as the Company may specify.
		
	Transfer of Option	  	 Prior to your death, only you may exercise this option. You cannot transfer or assign this option. For instance, you may not sell this option
or use it as security for a loan. If you attempt to do any of these things, this option will immediately become invalid. You may, however, dispose of this option in your will or by means of a written beneficiary designation (if authorized by the
Company and to the extent such beneficiary designation is valid under applicable law) which must be filed with the Company on the proper form; provided, however, that your beneficiary or a representative of your estate acknowledges and agrees in
writing in a form reasonably acceptable to the Company, to be bound by the provisions of this Agreement and the Plan as if such beneficiary or representative of the estate were you.

 
 Regardless of any marital property settlement agreement, the Company is not obligated to
honor a notice of exercise from your former spouse, nor is the Company obligated to recognize your former spouse’s interest in your option in any other way.

		
	No Retention Rights	  	You understand that neither this option nor this Agreement alters the at-will nature of your relationship with the Company. Your option or this Agreement does not give you the right to be
retained by the Company, a Parent, Subsidiary, or an Affiliate in any capacity. The Company and its Parents, Subsidiaries, and Affiliates reserve the right to terminate your Service at any time, with or without cause.
		
	Stockholder Rights	  	You, or your estate or heirs, have no rights as a stockholder of the Company until you have exercised this option by giving the required notice to the Company, paying the exercise price, and satisfying any applicable Tax-Related Items. No adjustments are made for dividends or other rights if the applicable record date occurs before you exercise this option, except as described in the Plan.
		
	Recoupment Policy	  	This option, and the shares acquired upon exercise of this option, shall be subject to any Company recoupment or clawback policy in effect from time to time.
		
	Adjustments	  	In the event of a stock split, a stock dividend or a similar change in Company common stock, the number of shares covered by this option and the exercise price per share will be adjusted pursuant to the Plan.

			
	Effect of Significant Corporate Transactions	  	If the Company is a party to a merger, consolidation, or certain change in control transactions, then this option will be subject to the applicable provisions of Article 9 of the Plan.
		
	Applicable Law	  	This Agreement will be interpreted and enforced under the laws of the State of Delaware (without regard to its choice-of-law provisions).
		
	The Plan and Other Agreements	  	 The text of the Plan is incorporated in this Agreement by reference.

 
 This Plan, this Agreement and the Grant Notice constitute the entire understanding
between you and the Company regarding this option. Any prior agreements, commitments or negotiations concerning this option are superseded. This Agreement may be amended only by another written agreement between the parties.

 BY ACCEPTING THIS OPTION GRANT, YOU AGREE TO ALL OF THE TERMS AND CONDITIONS DESCRIBED ABOVE AND IN THE
PLAN.EX-10.19

 Exhibit 10.19 

CFO 
 EMPLOYMENT
AGREEMENT 
 THIS AGREEMENT (the “Agreement”) is entered into by and between
BRIAN SILVER (the “Executive” or “you”) and TSCAN THERAPEUTICS, INC. (the “Company”), a
Delaware corporation and replaces and supersedes the employment agreement between the Executive and Company, dated February 1, 2021 (as amended, the “Prior Agreement”). 

1.    Duties and Scope of Employment. 

(a)    Position. For the term of his employment under this Agreement (the “Employment”),
the Company agrees to employ the Executive in the position Senior Vice-President and Chief Financial Officer. The Executive shall report to the Company’s Chief Executive Officer. Your start date will be May 3, 2021 (the “Start
Date”). 
 (b)     Obligations to the Company. During his Employment, the Executive
(i) shall devote his full business efforts and time to the Company, (ii) shall not engage in any other employment, consulting or other business activity that would create a conflict of interest with the Company, (iii) shall not assist
any person or entity in competing with the Company or in preparing to compete with the Company and (iv) shall comply with the Company’s policies and rules, as they may be in effect from time to time. The Executive will be able to serve on
one other company board of directors that has been approved in advance by the Company’s Chief Executive Officer. 

(c)    No Conflicting Obligations. The Executive represents and warrants to the Company that he is
under no obligations or commitments, whether contractual or otherwise, that are inconsistent with his obligations under this Agreement. The Executive represents and warrants to the Company that he has returned all property and confidential
information belonging to any prior employer. 
 (d)    Definitions. Certain capitalized terms are
defined in Section 12. 
 2.    Cash and Incentive Compensation. 

(a)    Salary. The Company shall pay the Executive as compensation for his services a base salary at
a gross annual rate of $457,500 (as may be adjusted, the “Base Salary”). Such salary shall be payable in accordance with the Company’s standard payroll procedures and shall be subject to adjustment pursuant to the Company’s
executive compensation policies in effect from time to time. 
 (b)    Bonus. You will be eligible
for an annual performance bonus of 40% of your annual base salary, subject to achievement of targets that you will develop for approval by the Company’s Board of Directors (the “Board”) or its Compensation Committee (the
“Committee”). Your 2021 bonus will be pro-rated based on your start date. Performance bonus goals and attainment of such goals will be evaluated and approved by the Committee and paid on an annual basis, with such payment, to the extent
earned, to be made within 2 1⁄2 months following the close of the applicable fiscal year, but only if you are still employed by the Company as of the date of
payment. The determinations of the Board or Committee with respect to your bonus will be final and binding. 

 (c)    Stock Options. Subject to the approval of
the Board or its Compensation Committee, you will be granted an option to purchase 2,053,621 shares of the Company’s Common Stock, subject to appropriate adjustment in the event of any stock dividend, stock split, combination or other similar
recapitalization (the “Option”). It is acknowledged that these options are in addition to the options granted to you pursuant to your service on the Board, which have their own independent vesting provisions. The exercise price per share
of the Option will be determined by the Board or its Compensation Committee when the Option is granted. The Option will be subject to the terms and conditions applicable to options granted under the Company’s 2018 Stock Plan (the
“Plan”), as described in the Plan and the applicable Stock Option Agreement. You will vest in 25% of the Option shares after 12 months of continuous service, and the balance will vest in equal monthly installments over the next 36 months
of continuous service, as described in the applicable Stock Option Agreement. 
 3.    Executive Benefits. During
his Employment, the Executive shall be eligible for paid time off in accordance with the Company’s flexible time off policy, as in effect from time to time, and for all official holidays. During his Employment, the Executive shall also be
eligible to participate in all company sponsored and executive benefit plans maintained by the Company, subject in each case to the generally applicable terms and conditions of the plan in question and to the determinations of any person or
committee administering such plan. 
 4.    Gifts. The Executive is not permitted to, directly or
indirectly, in connection with the performance of his duties, accept or demand commission, contribution, reimbursement or gifts in any form whatsoever from third parties. This does not apply to customary promotional gifts not exceeding a value of
$50. 
 5.    Term of Employment. 

(a)    Employment at Will. The Executive’s Employment with the Company shall be “at
will,” meaning that either the Executive or the Company shall be entitled to terminate the Executive’s Employment at any time and for any reason, with or without Cause. Any contrary representations that may have been made to the Executive
shall be superseded by this Agreement. This Agreement shall constitute the full and complete agreement between the Executive and the Company on the “at will” nature of the Executive’s Employment. Although Executive’s job duties,
title, compensation and benefits, as well as the Company’s personnel policies and procedures, may change from time to time, the “at will” nature of the Executive’s employment may only be changed in an express written agreement
signed by the Executive and a duly authorized officer of the Company (other than the Executive). The termination of the Executive’s Employment shall not limit or otherwise affect his obligations under Sections 7 and/or 8 below or his rights
under Section 6 below. 

 (b)    Rights upon Termination. Except as
expressly provided in Section 6 below, upon the termination of the Executive’s Employment, the Executive shall only be entitled to the compensation and benefits that the Executive has earned under this Agreement before the effective date
of the termination. The payments under this Agreement shall fully discharge all responsibilities of the Company to the Executive (other than payments of accrued and vested executive benefits, if any, under the Company’s executive benefit
plans). 
 6.    Termination Benefits. 

(a)    General. If you are subject to an Involuntary Termination, then you will be entitled to the
benefits described in Section 6(b). However, Section 6(b) will not apply unless you (i) have returned all Company property in your possession, and (ii) have executed a general release of all claims (with applicable carve-out for
continued indemnification, mutual non-disparagement and other customary exceptions) that you may have against the Company or persons affiliated with the Company. You must execute and return the release on or before the date specified by the Company
in the prescribed form (the “Release Deadline”). The Release Deadline will in no event be later than 50 days after your Separation. If you fail to return the release on or before the Release Deadline, or if you revoke the release, then you
will not be entitled to the benefits described in Section 6(b). Your obligation to provide the release will be waived and treated as satisfied if the Company has not delivered the initial form of release to you within ten days after your
employment ends. 
 (b)    Severance Payment. If you are subject to an Involuntary Termination,
then the Company will continue to pay you the Base Salary for twelve (12) months following your Separation (the “Severance Period”). The salary continuation payments will commence on the first payroll date following expiration of the
applicable revocation period of the release provided for in Section 6(a) and thereafter on the Company’s normal payroll schedule. In the event you are subject to an Involuntary Termination in the three (3) months prior to a Change in
Control, on a Change in Control or in the twelve (12) months following a Change in Control, then the Company will pay you a lump sum cash payment equal to (i) 1 times (x) Base Salary plus (y) annual target bonus plus
(ii) your pro-rata (number of days worked in in the fiscal year of Separation over 365) target bonus, subject to execution of the release. However, if the 50-day period described in Section 6(a) spans two (2) calendar years, then the
salary continuation payments or, if applicable, the lump sum payment will commence or be paid on the first payroll date following expiration of the applicable revocation period in the second calendar year. The Company’s obligation to make
payments during the Severance Period will cease immediately upon (i) your material breach of the PIIA (as defined below) or (ii) your acceptance of any paid employment or consulting engagement during any period in which the Company is
obligated to make such payments, and you hereby agree to immediately inform the Company in the event that you have accepted any such paid employment or consulting engagement. 

 (c)    Equity Awards. In the event you are
subject to an Involuntary Termination in the three (3) months prior to a Change in Control, on a Change in Control or in the twelve (12) months following a Change in Control, then all of your outstanding and unvested option shares and
equity awards issued shall be 100% vested and non-forfeitable. 
 (d)    COBRA. If you are subject
to an Involuntary Termination and you elect to continue your health insurance coverage under the Consolidated Omnibus Budget Reconciliation Act (“COBRA”) following your Separation, then the Company will pay the same percentage of your
monthly premium under COBRA, which is understood to potentially be higher than said premium for active employees, as it pays for active employees and their eligible dependents for the 12 months following your Separation. 

(e)    Accrued Rights. You will be entitled to receive the following upon termination of employment
for any reason: (i) accrued and unpaid Base Salary through the date of termination of employment; (ii) reimbursement for any unreimbursed business expenses; and (iii) such employee benefits, if any, to which the Executive may be
entitled under the applicable Company plans upon termination of employment. 
 7.    Documents and Company
Property. The Executive is prohibited from keeping in his possession in any way any correspondence, documents, other information carriers, copies thereof, and other goods made available by the Company or its affiliates to him (including, but not
limited to, credit cards, mobile communication devices, keys, documents, handbooks, financial data, plans, USB sticks or other information carriers, access cards and laptop computer), except to the extent that this is necessary for the performance
of his work for the Company. In any event, the Executive is obliged to immediately hand over such documents and other goods made available to him at the end of this Agreement or upon suspension of his active duties for any reason other than
documents relating to his own employment and compensation. 
 8.    Proprietary Information and Inventions
Agreement. The Executive and the Company entered into a Proprietary Information and Inventions Agreement, which shall be effective as of the Start Date (the “PIIA”) on the Company’s standard form. In the event of an Involuntary
Termination in connection with a Change in Control, the non-compete and non-solicitation restrictive covenants of the PIIA shall be null and void. 

9.    Reimbursement of Expenses. Your primary business location will be the Company’s corporate office,
currently located in Waltham, Massachusetts. You are eligible for reimbursement of up to $25,000 in documented travel expenses to the Company’s corporate office annually through the four-year anniversary of your start date, up to a maximum of
$100,000 in total, subject to applicable taxes. In addition, the Company will reimburse business expenses reasonably incurred in the performance of your duties in accordance with the Company’s standard practice and expense scheme in place at
the time (generally within 30 days after you have submitted appropriate documentation, which you must do within 30 days after incurring the expense) and, in any case, on or before the last day of the calendar year following the calendar year in
which the relevant expense is incurred. The Company will reimburse reasonable costs of the professional use of your (mobile) telephone. 

 10.    Successors. 

(a)    Company’s Successors. This Agreement shall be binding upon any successor (whether direct
or indirect and whether by purchase, lease, merger, consolidation, liquidation or otherwise) to all or substantially all of the Company’s business and/or assets. For all purposes under this Agreement, the term “Company” shall include
any successor to the Company’s business and/or assets which becomes bound by this Agreement. 

(b)    Executive’s Successors. This Agreement and all rights of the Executive hereunder shall
inure to the benefit of, and be enforceable by, the Executive’s personal or legal representatives, executors, administrators, successors, heirs, distributees, devisees and legatees. 

11.    Indemnification. During your employment by the Company and at all times thereafter, regardless of the reason
for termination, to the fullest extent permitted by its articles of incorporation and by applicable law, the Company shall indemnify you and hold you harmless against any cost, fee, expense, fine or penalty to which you may be subject as a result of
serving as an employee or officer of the Company or member of its Board and provide for you to be covered by the insurance or other indemnity policy applicable to officers or directors of the Company (including any rights to advances or
reimbursement of legal fees thereunder). The Company’s indemnification obligation shall survive any termination of your employment. 

12.    Definitions. The following terms shall have the meaning set forth below wherever they are used in this
Agreement: 
 (a)    Cause. The term “Cause” shall mean: 

(i)    any material breach by you of any agreement to which you and the Company are both parties that is
injurious to the Company; 
 (ii)    gross negligence in the performance of, or a willful failure to
perform, your services to the Company, which breach, negligence or failure, as applicable, is not cured within thirty (30) days following written notice by the Company; 

(iii)    commission by you of a felony or other crime involving moral turpitude; or 

(iv)    willful misconduct by you which has, or could reasonably be expected to have, a material adverse
effect upon the business, interests or reputation of the Company. 
 (b)    Change in Control. The
term “Change in Control” shall mean (i) any “person” (as such term is used in Sections 13(d) and 14(d) of the Exchange Act) becomes the “beneficial owner” (as defined in Rule 13d-3 of the Exchange Act),
directly or indirectly, of securities of the Company representing more than fifty percent (50%) of the 

 
total voting power represented by the Company’s then-outstanding voting securities; (ii) the consummation of a merger or consolidation of the Company with or into any other entity,
other than a merger or consolidation which would result in the voting securities of the Company outstanding immediately prior thereto continuing to represent (either by remaining outstanding or by being converted into voting securities of the
surviving entity or its parent) more than fifty percent (50%) of the total voting power represented by the voting securities of the Company or such surviving entity or its parent outstanding immediately after such merger or consolidation; or
(iii) the sale, transfer or other disposition of all or substantially all of the Company’s assets. 

(c)    Code. The term “Code” shall mean the Internal Revenue Code of 1986, as
amended. 
 (d)    Disability. The term “Disability” shall mean that the
Executive is unable to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment which can be expected to result in death or to last for a continuous period of not less than twelve months. 

(e)    Involuntary Termination. The term “Involuntary Termination” shall mean
either the Executive’s (i) Termination Without Cause or (ii) Resignation for Good Reason. 

(f)    Resignation for Good Reason. The term “Resignation for Good Reason” means a
Separation as a result of the Executive’s resignation within 12 months after one of the following conditions has come into existence without the Executive’s consent: 

(i)    a material diminution in your compensation (except for across-the-board reductions affecting the
Company’s similarly situated employees generally); 
 (ii)    a material diminution in your title,
duties, authority and responsibilities within the Company, including without limitation no longer reporting to the Company’s Chief Executive Officer; 

(iii)    relocation of your principal workplace by more than 50 miles away from any Company office; or 

(iv)    a material breach of the Company’s obligation under any agreement between the Company and you.

 A Resignation for Good Reason shall not be deemed to have occurred unless the Executive gives the Company written notice of the condition within 60 days
after the condition comes into existence and the Company fails to remedy the condition within 30 days after receiving the Executive’s written notice. 

(g)    Separation. The term “Separation” shall mean a “separation from service,”
as defined in the regulations under Section 409A of the Code. 

 (h)    “Termination Without Cause” The
term “Termination without Cause” means a Separation as a result of a termination of the Executive’s employment by the Company without Cause and other than as a result of Disability. 

13.    Miscellaneous Provisions. 

(a)    Notice. Notices and all other communications contemplated by this Agreement shall be in
writing and shall be deemed to have been duly given when personally delivered, when delivered via email to a Company domain email address or, following the Separation, to the Executive’s personal email address on file with Human Resources, when
delivered by FedEx with delivery charges prepaid, or when mailed by U.S. registered or certified mail, return receipt requested and postage prepaid. In the case of the Executive, mailed notices shall be addressed to him at the home address that he
most recently communicated to the Company in writing. In the case of the Company, mailed notices shall be addressed to its corporate headquarters, and all notices shall be directed to the attention of its Secretary. 

(b)    Modifications and Waivers. No provision of this Agreement shall be modified, waived or
discharged unless the modification, waiver or discharge is agreed to in writing and signed by the Executive and by an authorized officer of the Company (other than the Executive). No waiver by either party of any breach of, or of compliance with,
any condition or provision of this Agreement by the other party shall be considered a waiver of any other condition or provision or of the same condition or provision at another time. 

(c)    Whole Agreement. This Agreement supersedes and replaces any prior agreements, including
without limitation, the Prior Agreement, representations or understandings (whether written, oral, implied or otherwise) between the Executive and the Company and constitute the complete agreement between the Executive and the Company regarding the
subject matter set forth herein; provided, however, that notwithstanding anything that is contained in the PIIA, (i) the definition of “Cause” as set forth herein shall apply and control your employment, not the definition contained
in Section 4(d) of the PIIA; (ii) the Company’s obligation to pay 12 months of severance in the event of an Involuntary Termination shall apply and control without regard to anything contained in Section 5 of the PIIA, except the
second sentence of Section 5(a) of the PIIA (the “Dollar-for-Dollar Reduction”); (iii) Section 5 of the PIIA (other than the Dollar-for-Dollar Reduction, which shall always apply) shall only apply in the event that you
resign without “good reason”; and (iv) Section 8 of the PIIA, to the extent it provides for legal action in connection with Section 4(d)(iii) of the PIIA to be brought exclusively in a state or federal court in Boston,
Massachusetts, shall only apply in connection with an application for injunctive relief (should injunctive relief be necessary). 

(d)     Tax Matters. All payments made under this Agreement shall be subject to reduction to reflect
taxes or other charges required to be withheld by law. The Company intends that all payments and benefits provided under this Agreement or otherwise are exempt from, or comply with, with the requirements of Code Section 409A so that none of the
payments or benefits will be subject to the additional tax imposed 

 
under Code Section 409A, and any ambiguities herein will be interpreted in accordance with such intent. For purposes of Code Section 409A, each payment, installment or benefit payable
under this Agreement is hereby designated as a separate payment. In addition, if the Company determines that you are a “specified Executive” under Code Section 409A(a)(2)(B)(i) at the time of your Separation, then (i) any
severance payments or benefits, to the extent that they are subject to Code Section 409A, will not be paid or otherwise provided until the first business day following (A) expiration of the six-month period measured from your Separation or
(B) the date of your death and (ii) any installments that otherwise would have been paid or provided prior to such date will be paid or provided in a lump sum when the severance payments or benefits commence. The Company shall not have a
duty to design its compensation policies in a manner that minimizes your tax liabilities, and you agree not to make any claim against the Company or the Board related to tax liabilities arising from your compensation. 

(e)    280G Parachute Payments. If any payment or benefit that you would receive in connection with
a Change in Control from the Company or otherwise (“Payment”) would (i) constitute a “parachute payment” within the meaning of Section 280G of the Code, and (ii) but for this sentence, be subject to the excise tax
imposed by Section 4999 of the Code (the “Excise Tax”), then such Payment shall be equal to the Reduced Amount. The “Reduced Amount” shall be either (x) the largest portion of the Payment that would result in no portion
of the Payment being subject to the Excise Tax, or (y) the largest portion, up to and including the total, of the Payment, whichever amount, after taking into account all applicable federal, state and local employment taxes, income taxes, and
the Excise Tax (all computed at the highest applicable marginal rate), results in your receipt of the greatest economic benefit notwithstanding that all or some portion of the Payment may be subject to the Excise Tax. If a reduction in payments or
benefits constituting “parachute payments” is necessary so that the Payment equals the Reduced Amount, any reduction shall be applied first, on a pro rata basis, to amounts that constitute deferred compensation within the meaning of
Section 409A of the Code, and, in the event that the reductions pursuant to this Section 13(e) exceed payments that are subject to Section 409A of the Code, the remaining reductions shall be applied, on a pro rata basis, to any
other remaining payments. The Company’s determinations hereunder shall be final, binding and conclusive on all interested parties. 

(f)    Arbitration. Any controversy or claim arising out of this Agreement and any and all claims
relating to your employment with the Company will be settled by final and binding arbitration. The arbitration will take place in the Commonwealth of Massachusetts. The arbitration will be administered by the American Arbitration Association under
its National Rules for the Resolution of Employment Disputes. Any award or finding will be confidential. You and the Company agree to provide one another with reasonable access to documents and witnesses in connection with the resolution of the
dispute. You and the Company will share the costs of arbitration equally up to, for you, the filing fee to bring a civil action in the state courts of Massachusetts. Each party will be responsible for its own attorneys’ fees, and the arbitrator
may not award attorneys’ fees unless a statute or contract at issue specifically authorizes such an award. This Section 13(f) does not apply to claims for workers’ 

 
compensation benefits or unemployment insurance benefits. This Section 13(f) also does not apply to claims concerning the ownership, validity, infringement, misappropriation, disclosure,
misuse or enforceability of any confidential information, patent right, copyright, mask work, trademark or any other trade secret or intellectual property held or sought by either you or the Company (whether or not arising under the PIIA between you
and the Company). 
 (g)    Choice of Law and Severability. This Agreement shall be interpreted in
accordance with the laws of the Commonwealth of Massachusetts (except its provisions governing the choice of law). If any provision of this Agreement becomes or is deemed invalid, illegal or unenforceable in any applicable jurisdiction by reason of
the scope, extent or duration of its coverage or any other reason, then such provision shall be deemed amended to the minimum extent necessary to conform to applicable law so as to be valid and enforceable or, if such provision cannot be so amended
without materially altering the intention of the parties, then such provision shall be stricken and the remainder of this Agreement shall continue in full force and effect. If any provision of this Agreement is rendered illegal by any present or
future statute, law, ordinance or regulation (collectively the “Law”), then such provision shall be curtailed or limited only to the minimum extent necessary to bring such provision into compliance with the Law. All the other terms and
provisions of this Agreement shall continue in full force and effect without impairment or limitation. 

(h)    No Assignment. This Agreement and all rights and obligations of the Executive hereunder are
personal to the Executive and may not be transferred or assigned by the Executive at any time. The Company may assign its rights under this Agreement to any entity that assumes the Company’s obligations hereunder in connection with any sale or
transfer of all or a substantial portion of the Company’s assets to such entity. 

(i)    Counterparts. This Agreement may be executed in two or more counterparts, each of which shall
be deemed an original, but all of which together shall constitute one and the same instrument. 
 (Signatures on following
page) 

 IN WITNESS WHEREOF, each of the parties has executed this Agreement, in the case of
the Company by its duly authorized officer, as of the day and year first above written. 
  

 

			
	TSCAN THERAPEUTICS, INC.
		
	  Signature:	 	/s/ David Southwell

 
			
		
	  Title:	 	Chief Executive Officer

 
			
		
	  Date:	 	May 4, 2021

 
			
		
	EXECUTIVE	 	
	
	/s/ Brian Silver
	Brian Silver

 
			
		
	Date:	 	May 4, 2021

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00327-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00327-of-00352.parquet"}]]