system: You are a contract-analysis assistant performing a span-extraction task. You are given an excerpt from a commercial contract and the name of a clause type to locate within it.

Return the exact text of the requested clause, copied verbatim from the excerpt — identical wording and punctuation, with no paraphrasing, summarising, explanation, or added commentary.

The excerpt is one window of a much longer contract and often will not contain the requested clause. If the requested clause does not appear in this excerpt, respond with exactly: Not found.

Output only the extracted clause text, or the exact string `Not found.` — nothing else.

user: Contract excerpt:
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documents necessary for such Party to initiate, prosecute and maintain such action. If either Green Cross or MacroGenics initiates an enforcement action pursuant to Section 15.5(b), then the other Party shall cooperate to the extent reasonably necessary and at the first Parties' sole expense (except for the expenses of the non­controlling Party's counsel, if any). Upon the reasonable request of the Party instituting any such action, such other Party shall join the suit and can be represented in any such legal proceedings using counsel of its own choice. Each Party shall assert and not waive the joint defense privilege with respect to all communications between the Parties reasonably the subject thereof. (d) Status; Settlement. The Parties shall keep each other informed of the status of and of their respective activities regarding any enforcement action pursuant to Section 15.5(b). Neither Party shall settle any litigation or legal proceeding in the Territory to enforce MacroGenics Licensed Patents or MacroGenics Licensed Trademarks without the other Party's written authorization. 15.6 Defense (a) Notice of Allegations. Each Party shall notify the other in writing of any allegations it receives from a Third Party that the manufacture, production, use, development, sale or distribution of any Product or any technology or intellectual property licensed by a Party under this Agreement infringes the intellectual property rights of such Third Party. Such notice shall be provided promptly, but in no event after more than fifteen (15) business days, following receipt of such allegations. (b) Notice of Suit. In the event that a Party receives notice that it or any of its Affiliates have been individually named as a defendant in a legal proceeding by a Third Party alleging infringement of a Third Party's Patents or other intellectual property right as a result of the manufacture, production, use, development, sale or distribution of Products or any technology or intellectual property licensed by a Party under this Agreement, such Party shall immediately notify the other Party in writing and in no event notify such other Party later than *** after the receipt of such notice. Such written notice shall include a copy of any summons or complaint (or the equivalent thereof) received regarding the foregoing. Each Party shall assert and not waive the joint defense privilege with respect to all communications between the Parties reasonably the subject thereof. In such event, the Parties shall agree how best to mitigate or control the defense of any such legal proceeding; provided however, that if either Party or any of its Affiliates have been individually named as a defendant in a legal proceeding relating to *** = Portions of this exhibit have been omitted pursuant to a request for confidential treatment. An unredacted version of this exhibit has been filed separately with the Commission. 45 the alleged infringement of a Third Party's Patents or other intellectual property right as a result of the manufacture, production, use, development, sale or distribution of Products, the other Party shall be allowed to join in such action, at its own expense. (c) Status; Settlement. The Parties shall keep each other informed of the status of and of their respective activities regarding any litigation or settlement thereof initiated by a Third Party in the Territory concerning a Party's manufacture, production, use, development, sale or distribution of Products or any technology or intellectual property licensed by a Party under this Agreement; provided, however, that no settlement or consent judgment or other voluntary final disposition of a suit under this Section 15.6(c) may be undertaken by a Party without the consent of the other Party which consent shall not be unreasonably withheld or delayed. 16. TERMS AND TERMINATION 16.1 Term. Unless earlier terminated, this Agreement shall continue in effect until the expiration of the Royalty Term as defined in Section 1.87 ("Term"), and thereafter Green Cross has no remaining payment obligations with respect to the Products pursuant to Section 8.5 above and MacroGenics shall have no further obligations hereunder. 16.2 Termination for Change in Control of Green Cross. In the event of a Change in Control involving Green Cross, Green Cross shall provide prompt written notice to MacroGenics following such Change in Control, and MacroGenics may, in its sole discretion, terminate this Agreement by providing written notice to Green Cross within *** of MacroGenics' receipt of such written notice of the Change in Control. 16.3 Termination for Change in Control of MacroGenics. In the event of a Change in Control involving MacroGenics, MacroGenics shall provide prompt written notice to Green Cross
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Extract the exact clause related to "Expiration Date" from the excerpt above.

assistant: Unless earlier terminated, this Agreement shall continue in effect until the expiration of the Royalty Term as defined in Section 1.87 ("Term"), and thereafter Green Cross has no remaining payment obligations with respect to the Products pursuant to Section 8.5 above and MacroGenics shall have no further obligations hereunder.