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:
"""
the Product by the beginning of a following contract year, Cremer may refuse to deliver the Product to Ultragenyx until the Parties agreed on a respective price. 3) Payments shall be made by Ultragenyx in Euro and within [***] days after receipt of a proper invoice. 4) Transfer of title with respect to any Product shall be subject to full payment and settlement of all claims Cremer may have against Ultragenyx in connection with the execution of this Agreement. Article 4 Specification; Warranties; Cremer's Liability; Indemnification 1) The Parties assume that the Product constitutes an active pharmaceutical ingredient in the meaning of Sec. 4 para. 19 AMG. Ultragenyx shall process the Product into a pharmaceutical product in the meaning of Sec. 2 AMG and market the processed Product as a pharmaceutical product in the meaning of Sec 2 AMG and to perform clinical trials. Cremer does not participate in the processing, manufacturing and marketing of the respective pharmaceutical product or in the clinical trials. [***] Certain information in this document has been omitted and filed separately with the Securities and Exchange Commission. Confidential treatment has been requested with respect to the omitted portions. 2 2) Upon execution of this Agreement and any purchase order, Cremer shall provide Ultragenyx with following documentation regarding the Product: Certificate of Analysis and the applicants' part of the Drug Master File once compiled. 3) Cremer represents and warrants that all quantities of Product delivered under the Agreement were manufactured in accordance with GMP. The Product shall be free from defects if it is within the specifications according to Annex A. 4) Cremer represents and warrants that it has not received any written notice from a third party alleging that the manufacture, use or sale of the Product infringes intellectual property rights of a third party. 5) Ultragenyx will perform final release of the Product. Ultragenyx may rely on the documentation provided by Cremer and Ultragenyx will not need to independently test the Product unless Ultragenyx determines such independent testing is necessary. In the event that the Product fails to conform to the Product Specifications, and/or GMP, Ultragenyx may reject the Product by giving written notice to Cremer within [***] days after receipt of the Product and all documentation (except such [***] day period will not apply for any latent defect). Within [***] days following receipt of the rejected and returned Product from Ultragenyx, Cremer will, at Ultragenyx's choice, replace such quantity of Product with Product conforming to the Product Specifications, and GMP or refund Ultragenyx the Price paid for such Product. 6) Cremer does not warrant or represent that the Product is effective in a pharmaceutical way within the meaning of Sec. 4 para. 19 AMG. Cremer does not warrant or represent that the Product is safe in a pharmaceutical and pharmacological way. Cremer does not warrant or represent that the Product is suitable for the intended Purpose by Ultragenyx. Cremer is not a pharmaceutical manufacturer within the meaning of Sec. 4 para. 18 AMG. Cremer's liability in connection with the Purpose and the processing and marketing of a pharmaceutical product is excluded. No. 9 below applies. 7) Except for a claim arising out of Cremer's intentional misconduct or gross negligence under this Agreement, in the event of legal proceedings being instituted against Cremer by a third party arising out of Ultragenyx's development, processing and commercialization of the Product, Ultragenyx shall indemnify and keep indemnified Cremer in full against all damages, losses, injuries, costs and expenses in connection with such legal proceedings. Cremer will inform Ultragenyx about any legal proceedings being instituted against Cremer without delay. Ultragenyx shall control the respective legal proceedings but shall not settle any claim that admits fault on behalf of Cremer without Cremer's consent (not be unreasonably withheld). [***] Certain information in this document has been omitted and filed separately with the Securities and Exchange Commission. Confidential treatment has been requested with respect to the omitted portions. 3 8) In the event of legal proceedings being instituted against Ultragenyx by a third party arising out of Cremer's intentional misconduct or gross negligence under this Agreement, Cremer shall indemnify and keep indemnified Ultragenyx in full against all damages, losses, injuries, costs and expenses in connection with such legal proceedings. Ultragenyx will inform Cremer about any legal proceedings being instituted against Ultragenyx without delay. Cremer shall control the respective legal proceedings but shall not settle any claim without Ultragenyx's consent (not be unreasonably withheld). 9) Cremer's liability arising from this Agreement is
"""

Extract the exact clause related to "Warranty Duration" from the excerpt above.

assistant: In the event that the Product fails to conform to the Product Specifications, and/or GMP, Ultragenyx may reject the Product by giving written notice to Cremer within [***] days after receipt of the Product and all documentation (except such [***] day period will not apply for any latent defect).