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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reason except by EKR pursuant to Section 16.1(a), EKR shall promptly transfer the Transferred NDA and related regulatory documentation to PPI in accordance with Section 17.1(e). 3.3 Maintenance of Transferred NDA. The Parties acknowledge that prior to the Agreement Date, PPI was responsible at its own cost and expense for maintaining and updating the Transferred NDA, and agree that PPI shall retain all liabilities with respect to the foregoing obligations to the extent relating to periods prior to the Agreement Date. Commencing as of the Agreement Date, EKR shall, at its own cost and expense, maintain and update the Transferred NDA and be responsible for all liabilities with respect to the foregoing obligations to the extent relating to periods after the Agreement Date. 3.4 Assistance. PPI shall, at EKR's cost and expense, provide EKR with all assistance, information and guidance, including where appropriate direct access to employees of and consultants to PPI and its Affiliates and shall use reasonable efforts to obtain such assistance and access from any sub-contractors of PPI and its Affiliates (including for the avoidance of doubt any manufacturers of the Product) which is reasonably necessary in relation to the conduct of any post-marketing or Phase IV studies to be conducted by EKR in the Territory or otherwise in connection with the discharge of EKR's obligations under the terms of this Agreement (including, but not limited to, the maintenance of the Transferred NDA); provided, however, that any such post-marketing or Phase IV studies to be conducted by EKR shall be at EKR's sole cost and expense. Any labor costs of PPI employees related to this assistance shall be reimbursed by EKR at a rate of [**] dollars ($[**]) per hour. PPI represents and warrants that as of the Agreement Date, except for the studies set forth on Schedule X attached hereto (the "Required Studies"), no post- marketing or Phase IV studies are required by any applicable Regulatory Authority to be conducted with respect to the Product. EKR shall be responsible for the conduct of the Required Studies after the Agreement Date, at its own expense, in accordance with the requirements of the applicable Regulatory Authorities. PPI shall be responsible for all costs and liabilities incurred prior to the Agreement Date with respect to the Required Studies, and shall indemnify and hold harmless EKR from such costs and liabilities. Promptly after the Agreement Date, PPI shall provide EKR with copies of all agreements relating to the Required Studies and shall assign such agreements to EKR if and to the extent (i) such agreements are assignable in accordance with their terms and (ii) requested by EKR. -16- 3.5 Adverse Events. PPI shall at its own cost and expense promptly provide EKR with all information in its possession or otherwise coming to its attention relating to the occurrence of a serious adverse event or an adverse event (in any jurisdiction throughout the world) in connection with the Product. PPI shall be responsible, to the extent required by Applicable Laws, to report all charges, complaints or claims reportable to the FDA relating to the Product, to the extent such charges, complaints or claims are made prior to the Agreement Date. EKR shall be responsible, to the extent required by Applicable Laws, to report all charges, complaints or claims reportable to the FDA relating to the Product, to the extent such charges, complaints or claims are made after the Agreement Date. 3.6 Reserved. 3.7 Delivery of Materials. The Parties acknowledge that prior to the Agreement Date, PPI has delivered to EKR (i) all existing PPI produced Promotional Materials (if any) and (ii) any existing market research in its possession related to the Product. -17- 3.8 Customer Orders. PPI shall at its own cost and expense during the Term, promptly forward to EKR any customer orders or inquiries for the Product within the Territory received after the Effective Date and shall inform any customers ordering the Product that EKR is now distributing the Product and provide such customers with EKR's address and telephone number. 3.9 Payment of Third Party Royalties. During the Term, PPI shall be solely responsible for and pay any royalties or other amounts due to Third Parties related to the Product and shall indemnify and hold EKR harmless from any claims arising from or related thereto. 3.10 Customer Returns. PPI shall at its own cost and expense be responsible for all customer returns of Product sold prior to the Effective Date. 3.11 Governmental Rebates. PPI shall at its own cost
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Extract the exact clause related to "Anti-Assignment" from the excerpt above.