Amendment No. 1 to Collaborative Research and License Agreement between the Registrant and Biogen MA, Inc., dated February 25, 2020

Exhibit 10.11

[***] Certain information in this document has been omitted from this exhibit because it is both (i) not material and (ii) would be competitively harmful if publicly disclosed.

AMENDMENT NO. 1 TO
COLLABORATIVE RESEARCH AND LICENSE AGREEMENT

THIS AMENDMENT NO. 1 TO COLLABORATIVE RESEARCH AND LICENSE AGREEMENT ("Amendment") is made as of February 25, 2020, by and among C4 Therapeutics, Inc., a Delaware corporation ("C4") and Biogen MA Inc., a Massachusetts corporation ("Biogen").

RECITALS

WHEREAS, C4 and Biogen are Parties to that certain Collaborative Research and License Agreement, having an Effective Date of December 28, 2018 (the "Agreement");

WHEREAS, the Parties contemplate that Biogen will provide one or more target binding moiety compounds, developed by Biogen pursuant to internal Biogen non-Degrader activities and programs, to be used in the discovery and/or development of Degraders pursuant to the Agreement;

WHEREAS, Biogen owns certain intellectual property, including know-how and patent rights, covering Biogen's target binding moiety compounds;

WHEREAS, Biogen and C4 understand and agree that Biogen will retain exclusive ownership of any target binding moiety compound provided by Biogen, including any improvements, modifications, and/or enhancements thereto, and to any intellectual property thereon, as well as the exclusive right to use any such target binding moiety compound and intellectual property thereon in connection with research and development programs other than degrader programs;

WHEREAS, pursuant to Section 13.2 of the Agreement, no amendment of the Agreement shall be effective unless in a writing signed by C4 and Biogen.

NOW, THEREFORE, the Parties hereto agree as follows:

Unless otherwise indicated herein, words and terms which are defined in the Agreement shall have the same meaning where used herein.

2.1  The following definitions are to be added:

1.193  "Biogen Target Binding Moiety" means any moiety that is directed to and binds to a particular Collaboration Target and that is Controlled by Biogen or its Affiliates and includes any improvement, modification or enhancement to such moiety made by either Party or its Affiliates.

1.194  "Biogen Target Binding Moiety Intellectual Property" means Intellectual Property Covering a Biogen Target Binding Moiety. For the avoidance of doubt, Biogen Target Binding Moiety Intellectual Property shall be excluded from Joint Technology and Assigned Platform Technology

2.2 The definition of "Degrader" shall be replaced in its entirety as follows:

1.77 "Degrader" means with respect to a Collaboration Target, a compound comprising (a) a C4 Target Binding Moiety or a Biogen Target Binding Moiety, (b) optionally, a Linker, and (c) an E3 Ligase Binding Moiety that degrades such Collaboration Target.

2.3: The definition of "Biogen Know-How" shall be replaced in its entirety as follows:

1.23 "Biogen Know-How" means (i) any Know-How Controlled by Biogen or any of its Affiliates, whether or not developed or acquired by Biogen or any of its Affiliates before or after the Effective Date, including all Biogen Collaboration Know-How, Product­ Specific Know-How, and Target Specific Know-How; and (ii) any Know-How relating to a Biogen Target Binding Moiety Controlled by Biogen or any of its Affiliates and/or developed or invented during the Term by C4's or its Affiliates', licensees', Sublicensees', or Subcontractors' employees, agents, or independent contractors, or any Persons contractually required to assign or license such Know-How to C4 or any Affiliate of C4, and such Know-How shall fall within the scope of Biogen Target Binding Moiety Intellectual Property.

2.4 The term "Target Binding Moiety" shall be replaced with the term "C4 Target Binding Moiety" throughout the Agreement and the term "C4 Target Binding Moiety" shall have the same definition of "Target Binding Moiety" set forth in Section 1.182 of the Agreement.

12.5.4 Biogen Target Binding Moiety and Biogen Target Binding Moiety Intellectual Property License. For the avoidance of doubt, the Parties agree that upon termination of the Agreement in whole or in part with respect to one or more Development Candidates, Products, or Collaboration Targets in accordance with Section 12:

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(i)all rights, title and interests in the Biogen Target Binding Moiety and Biogen Target Binding Moiety Intellectual Property shall continue to be owned by Biogen; and

(ii)To the extent Biogen's rights to Biogen Target Binding Moiety Intellectual Property permit, Biogen will grant to C4 a limited, non-exclusive, non-commercial, research license, with no right to sublicense, under Biogen Target Binding Moiety Intellectual Property, solely to make and use a Biogen Target Binding Moiety that was provided to C4 by Biogen under the Agreement for C4's internal, non-commercial, research purposes and limited to the extent that such Biogen Target Binding Moiety is an essential component of a Degrader and solely for the purpose of making such Degrader (the "C4 Research License"). [***]

(iii)In the event that Biogen, pursuant to an internal non-Degrader activity or program, identifies as a development candidate a Biogen Target Binding Moiety that had been provided to C4 under the Agreement, the C4 Research License described in Section 12.5.4 with respect to such Biogen Target Binding Moiety shall terminate immediately upon written notice by Biogen to C4 of such identification.

[Signature Page Follows]

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IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of the date first above written.