Regeneron Patents. Regeneron will be solely responsible, ​, for preparing, filing, prosecuting (including provisional, reissue, reexamination, continuing, divisional, continuation, continuation-in-part, and substitute applications and any foreign counterparts thereof), and maintaining all Regeneron Patents, and conducting any interferences and oppositions or similar proceedings relating to any Regeneron Patents. CytomX acknowledges and agrees that ​.

By Regeneron. Regeneron agrees to defend CytomX, its Affiliates and their respective directors, officers, employees and agents (the “CytomX Indemnified Parties”), at Regeneron’s cost and expense, and will indemnify and hold CytomX and the other CytomX Indemnified Parties harmless from and against any Losses in connection with any Third Party Claims to the extent arising out of or resulting from ​; except, in each of [(a) through (c)], to the extent such Losses result from any of [clauses (a) through (c) of Section 10.1.1] above.

Regeneron Sales Reports. After the First Commercial Sale of the first Licensed Product by Regeneron and until expiration or termination of this Agreement, Regeneron shall prepare and (within ​ days after the end of each Calendar Quarter) deliver to CytomX reports of the sale of Licensed Products by Regeneron or its Affiliates, and their respective Sublicensees for each Calendar Quarter together with the corresponding royalty payment or other consideration to be paid to CytomX, specifying on a Licensed Product-by- Licensed Product and country-by-country basis, a detailed and itemized calculation of Net Sales. All such information and reports shall be treated as Regeneron’s Confidential Information pursuant to the terms of [Article 12].

License Grants to Regeneron. Subject to the terms and conditions of this Agreement, CytomX hereby grants and shall grant to Regeneron an exclusive (even as to CytomX and its Affiliates, except as expressly set forth in this Agreement and subject to CytomX and its Affiliates retaining the non-exclusive rights reasonably necessary or useful to perform CytomX’s obligations under this Agreement and any Work Plan) royalty-bearing, sublicensable (but only in accordance with [Section 4.2]), license under the CytomX IP to Exploit Licensed Products in the Licensed Field in the Territory during the Term. Notwithstanding the foregoing, the CytomX Know-How shall be sublicensable only in connection with the rights of Regeneron with respect to Products and not with respect to any other products or services. Notwithstanding anything to the contrary in [Section 4.1.1] or elsewhere in this Agreement, ​.

Regeneron Background Improvements IP. Regeneron shall solely own all right, title and interest in and to any and all Regeneron Background Improvements IP arising under this Agreement, including any Patent Rights with respect thereto and the right to pursue the same. CytomX hereby assigns to Regeneron all right, title and interest in and to any such Regeneron Background Improvements IP; provided, that if such assignment is prohibited by applicable Law, then CytomX shall grant, and hereby does grant, to Regeneron, a perpetual, irrevocable, exclusive (even as to CytomX), worldwide, royalty-free, fully paid-up license, with the right to grant sublicenses through multiple tiers, under such Regeneron Background Improvement IP. CytomX will cooperate with Regeneron to execute any agreements, instruments and documents as may be reasonably required to perfect Regeneron’s right, title and interest in and to such Regeneron Background Improvements IP.

Other Termination. Regeneron may terminate this Agreement with respect to a given Collaboration Program or Licensed Product effective # upon ​ days’ written notice to CytomX in the event that Regeneron in good faith believes it is not advisable for Regeneron to continue to Develop or Commercialize any Licensed Products in such Collaboration Program, or # immediately upon written notice to CytomX in the event that CytomX or any of its Sublicensees or Affiliates, or any Person acting on CytomX’s behalf, initiates or asserts any Regeneron Patent Challenge and fails to initiate rescission of such Regeneron Patent Challenge within ​ Business Days after such written notice and thereafter fails to rescind such Regeneron Patent Challenge within ​ days after such written notice. In the event any Sublicensee (or any Person acting on its behalf) of CytomX initiates or asserts any Regeneron Patent Challenge in any forum, CytomX shall, upon written request by Regeneron, immediately terminate the applicable sublicense agreement with such Sublicensee.

​ Activities. Outside of the activities conducted pursuant to this Agreement, Regeneron shall not # make or use any ​ shared with Regeneron pursuant to this Agreement except as part of a Product, and # under any circumstances optimize or modify any ​ provided to Regeneron under this Agreement.

Records. Regeneron will keep complete and accurate records of all royalty, milestone and other payments required under this Agreement, for a period of ​ years after the end of the Calendar Year in which such payment was due. Regeneron shall require its Affiliates, and its and their respective Sublicensees to retain and provide to Regeneron all records of payments

If Regeneron is the paying Party:

Notice and Cooperation. CytomX shall provide to Regeneron prompt written notice of any actual, potential, or threatened infringement of the Product Trademarks in the Territory and of any actual or threatened claim that the use of the Product Trademarks in the Territory violates the rights of any Third Party, promptly after becoming aware of the foregoing. CytomX agrees to cooperate fully with Regeneron, at Regeneron’s sole cost and expense, with respect to any enforcement action or defense commenced pursuant to this [Section 8.9].