EX-10.3



 Exhibit 10.3 

Constellation Pharmaceuticals, Inc. 

Incentive Stock Option Agreement 

Granted Under 2008 Stock Incentive Plan 

1.    Grant of Option. 

This agreement evidences the grant by Constellation Pharmaceuticals, a Delaware corporation (the “Company”), on
[                ] (the “Grant Date”) to [            ], an employee of the Company (the
“Participant”), of an option to purchase, in whole or in part, on the terms provided herein and in the Company’s 2008 Stock Incentive Plan (the “Plan”), a total of
[            ] shares (the “Shares”) of common stock, $0.0001 par value per share, of the Company (“Common Stock”) at
$[        ] per Share. Unless earlier terminated, this option shall expire at 5:00 p.m., Eastern time, on
[                ] (the “Final Exercise Date”). 

It is intended that the option evidenced by this agreement shall be an incentive stock option as defined in Section 422 of the Internal
Revenue Code of 1986, as amended, and any regulations promulgated thereunder (the “Code”). Except as otherwise indicated by the context, the term “Participant”, as used in this option, shall be deemed to include any person who
acquires the right to exercise this option validly under its terms. 
 2.    Vesting Schedule. 

(a)    Option Exercise Schedule. This option will become exercisable (“vest”) as to 6.25% of the original
number of Shares at the end of the first three-month period following [                    ] (the “Vesting Commencement Date”) and as to an
additional 6.25% of the original number of Shares at the end of each successive three-month period following thereafter until the fourth anniversary of the Vesting Commencement Date. 

The right of exercise shall be cumulative so that to the extent the option is not exercised in any period to the maximum extent permissible it
shall continue to be exercisable, in whole or in part, with respect to all Shares for which it is vested until the earlier of the Final Exercise Date or the termination of this option under Section 3 hereof or the Plan. 

3.    Exercise of Option. 

(a)    Form of Exercise. Each election to exercise this option shall be in writing, signed by the Participant, and
received by the Company at its principal office, accompanied by this agreement, and payment in full in the manner provided in the Plan. The Participant may purchase less than the number of shares covered hereby, provided that no partial exercise of
this option may be for any fractional share. 
 (b)    Continuous Relationship with the Company Required. Except
as otherwise provided in this Section 3, this option may not be exercised unless the Participant, at the time he or she exercises this option, is, and has been at all times since the Grant Date, an employee or officer of, or consultant or
advisor to, the Company or any parent or subsidiary of the Company as defined in Section 424(e) or (f) of the Code (an “Eligible Participant”). 
  







 (c)    Termination of Relationship with the Company. If the
Participant ceases to be an Eligible Participant for any reason, then, except as provided in paragraphs (d) and (e) below, the right to exercise this option shall terminate three months after such cessation (but in no event after
the Final Exercise Date), provided that this option shall be exercisable only to the extent that the Participant was entitled to exercise this option on the date of such cessation. Notwithstanding the foregoing, if the Participant,
prior to the Final Exercise Date, violates the non-competition or confidentiality provisions of any employment contract, confidentiality and nondisclosure agreement or other agreement between the Participant
and the Company, the right to exercise this option shall terminate immediately upon written notice to the Participant from the Company describing such violation. 

(d)    Exercise Period Upon Death or Disability. If the Participant dies or becomes disabled (within the meaning of
Section 22(e)(3) of the Code) prior to the Final Exercise Date while he or she is an Eligible Participant and the Company has not terminated such relationship for “cause” as specified in paragraph (e) below, this option shall be
exercisable, within the period of one year following the date of death or disability of the Participant, by the Participant (or in the case of death by an authorized transferee), provided that this option shall be exercisable only to
the extent that this option was exercisable by the Participant on the date of his or her death or disability, and further provided that this option shall not be exercisable after the Final Exercise Date. 

(e)    Termination for Cause. If, prior to the Final Exercise Date, the Participant’s employment is terminated
by the Company for Cause (as defined below), the right to exercise this option shall terminate immediately upon the effective date of such termination of employment. If, prior to the Final Exercise Date, the Participant is given notice by the
Company of the termination of his or her employment by the Company for Cause, and the effective date of such employment termination is subsequent to the date of delivery of such notice, the right to exercise this option shall be suspended from the
time of the delivery of such notice until the earlier of (i) such time as it is determined or otherwise agreed that the Participant’s employment shall not be terminated for Cause as provided in such notice or (ii) the effective date
of such termination of employment (in which case the right to exercise this option shall, pursuant to the preceding sentence, terminate upon the effective date of such termination of employment). If the Participant is party to an employment or
severance agreement with the Company that contains a definition of “cause” for termination of employment, “Cause” shall have the meaning ascribed to such term in such agreement. Otherwise, “Cause” shall mean willful
misconduct by the Participant or willful failure by the Participant to perform his or her responsibilities to the Company (including, without limitation, breach by the Participant of any provision of any employment, consulting, advisory,
nondisclosure, non-competition or other similar agreement between the Participant and the Company), as determined by the Company, which determination shall be conclusive. The Participant shall be considered to
have been discharged for Cause if the Company determines, within 30 days after the Participant’s resignation, that discharge for cause was warranted. 

  
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 4.    Company Right of First Refusal. 

(a)    Notice of Proposed Transfer. If the Participant proposes to sell, assign, transfer, pledge, hypothecate or
otherwise dispose of, by operation of law or otherwise (collectively, “transfer”) any Shares acquired upon exercise of this option, then the Participant shall first give written notice of the proposed transfer (the “Transfer
Notice”) to the Company. The Transfer Notice shall name the proposed transferee and state the number of such Shares the Participant proposes to transfer (the “Offered Shares”), the price per share and all other material terms and
conditions of the transfer. 
 (b)    Company Right to Purchase. For 30 days following its receipt of such
Transfer Notice, the Company shall have the option to purchase all or part of the Offered Shares at the price and upon the terms set forth in the Transfer Notice. In the event the Company elects to purchase all or part of the Offered Shares, it
shall give written notice of such election to the Participant within such 30-day period. Within 10 days after his or her receipt of such notice, the Participant shall tender to the Company at its principal
offices the certificate or certificates representing the Offered Shares to be purchased by the Company, duly endorsed in blank by the Participant or with duly endorsed stock powers attached thereto, all in a form suitable for transfer of the Offered
Shares to the Company. Promptly following receipt of such certificate or certificates, the Company shall deliver or mail to the Participant a check in payment of the purchase price for such Offered Shares; provided that if the terms of
payment set forth in the Transfer Notice were other than cash against delivery, the Company may pay for the Offered Shares on the same terms and conditions as were set forth in the Transfer Notice; and provided further that any delay
in making such payment shall not invalidate the Company’s exercise of its option to purchase the Offered Shares. 

(c)    Shares Not Purchased By Company. If the Company does not elect to acquire all of the Offered Shares, the
Participant may, within the 30-day period following the expiration of the option granted to the Company under subsection (b) above, transfer the Offered Shares which the Company has not elected to acquire
to the proposed transferee, provided that such transfer shall not be on terms and conditions more favorable to the transferee than those contained in the Transfer Notice. Notwithstanding any of the above, all Offered Shares transferred
pursuant to this Section 4 shall remain subject to the right of first refusal set forth in this Section 4 and such transferee shall, as a condition to such transfer, deliver to the Company a written instrument confirming that such
transferee shall be bound by all of the terms and conditions of this Section 4. 
 (d)    Consequences of Non-Delivery. After the time at which the Offered Shares are required to be delivered to the Company for transfer to the Company pursuant to subsection (b) above, the Company shall not pay any dividend to
the Participant on account of such Offered Shares or permit the Participant to exercise any of the privileges or rights of a stockholder with respect to such Offered Shares, but shall, insofar as permitted by law, treat the Company as the owner of
such Offered Shares. 
 (e)    Exempt Transactions. The following transactions shall be exempt from the
provisions of this Section 4: 
 (1)    any transfer of Shares to or for the benefit of any spouse, child or
grandchild of the Participant, or to a trust for their benefit; 

  
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 (2)    any transfer pursuant to an effective registration statement filed by
the Company under the Securities Act of 1933, as amended (the “Securities Act”); and 
 (3)    the sale of all
or substantially all of the outstanding shares of capital stock of the Company (including pursuant to a merger or consolidation); 
 provided,
however, that in the case of a transfer pursuant to clause (1) above, such Shares shall remain subject to the right of first refusal set forth in this Section 4 and such transferee shall, as a condition to such transfer, deliver to
the Company a written instrument confirming that such transferee shall be bound by all of the terms and conditions of this Section 4. 

(f)    Assignment of Company Right. The Company may assign its rights to purchase Offered Shares in any particular
transaction under this Section 4 to one or more persons or entities. 
 (g)    Termination. The provisions
of this Section 4 shall terminate upon the earlier of the following events: 
 (1)    the closing of the sale of
shares of Common Stock in an underwritten public offering pursuant to an effective registration statement filed by the Company under the Securities Act; or 

(2)    the sale of all or substantially all of the outstanding shares of capital stock, assets or business of the Company,
by merger, consolidation, sale of assets or otherwise (other than a merger or consolidation in which all or substantially all of the individuals and entities who were beneficial owners of the Company’s voting securities immediately prior to
such transaction beneficially own, directly or indirectly, more than 75% (determined on an as-converted basis) of the outstanding securities entitled to vote generally in the election of directors of the
resulting, surviving or acquiring corporation in such transaction). 
 (h)    No Obligation to Recognize Invalid
Transfer. The Company shall not be required (1) to transfer on its books any of the Shares which shall have been sold or transferred in violation of any of the provisions set forth in this Section 4, or (2) to treat as owner of
such Shares or to pay dividends to any transferee to whom any such Shares shall have been so sold or transferred. 

(i)    Legends. The certificate representing Shares shall bear a legend substantially in the following form (in
addition to, or in combination with, any legend required by applicable federal and state securities laws and agreements relating to the transfer of the Company securities): 

“The shares represented by this certificate are subject to a right of first refusal in favor of the Company, as provided in a certain
stock option agreement with the Company.” 

  
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 5.    Agreement in Connection with Initial Public Offering. 

The Participant agrees, in connection with the initial underwritten public offering of the Common Stock pursuant to a registration statement under the
Securities Act, (i) not to (a) offer, pledge, announce the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, or
otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or any other securities of the Company or (b) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of
ownership of shares of Common Stock or other securities of the Company, whether any transaction described in clause (a) or (b) is to be settled by delivery of securities, in cash or otherwise, during the period beginning on the date of the
filing of such registration statement with the Securities and Exchange Commission and ending 180 days after the date of the final prospectus relating to the offering (plus up to an additional 34 days to the extent requested by the managing
underwriters for such offering in order to address Rule 2711(f) of the National Association of Securities Dealers, Inc. or any similar successor provision), and (ii) to execute any agreement reflecting clause (i) above as may be requested
by the Company or the managing underwriters at the time of such offering. The Company may impose stop-transfer instructions with respect to the shares of Common Stock or other securities subject to the foregoing restriction until the end of the “lock-up” period. 
 6.    Tax Matters. 

(a)    Withholding. No Shares will be issued pursuant to the exercise of this option unless and until the
Participant pays to the Company, or makes provision satisfactory to the Company for payment of, any federal, state or local withholding taxes required by law to be withheld in respect of this option. 

(b)    Disqualifying Disposition. If the Participant disposes of Shares acquired upon exercise of this option
within two years from the Grant Date or one year after such Shares were acquired pursuant to exercise of this option, the Participant shall notify the Company in writing of such disposition. 

7.    Nontransferability of Option. 

This option may not be sold, assigned, transferred, pledged or otherwise encumbered by the Participant, either voluntarily or by operation of
law, except by will or the laws of descent and distribution, and, during the lifetime of the Participant, this option shall be exercisable only by the Participant. 

8.    Provisions of the Plan. 

This option is subject to the provisions of the Plan (including the provisions relating to amendments to the Plan), a copy of which is
furnished to the Participant with this option. 

  
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 IN WITNESS WHEREOF, the Company has caused this option to be executed under its corporate seal by
its duly authorized officer. This option shall take effect as a sealed instrument. 
  

			
	Constellation Pharmaceuticals, Inc.


 
			
		
	By:	 	  

	Name:	 	
	Title	 	



  
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 PARTICIPANT’S ACCEPTANCE 

The undersigned hereby accepts the foregoing option and agrees to the terms and conditions thereof. The undersigned hereby acknowledges
receipt of a copy of the Company’s 2008 Stock Incentive Plan. 
  

			
	PARTICIPANT


 
			
	
	  





			
		
	Address:	 	  

		
		 	  




  
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