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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or conditions of this Agreement must be in writing and will not be construed as a continuing waiver of other breaches of the same nature or other covenants or conditions of this Agreement. 5.4. Relationship of Parties This Agreement is not intended to create, nor should it be construed as creating, a joint venture, partnership or similar relationship between the parties. The Agent will act solely as an independent agent and will have no right to bind the Company in any way or to represent that the Company is in any way responsible for any acts or omissions of the Agent. 5.5. Force Majeure. Notwithstanding any other provision of this Agreement, if either the Company or the Agent is delayed in or prevented from fulfilling any of its obligations hereunder by reason of any cause beyond its reasonable control (including, but not limited to acts of God, fire, third party strike, flood, delay of transportation or inability to obtain necessary raw materials through normal commercial channels), then that party will not be liable under this Agreement for damages resulting from such delay or failure. Each party will promptly notify the other upon becoming aware of the occurrence of any such cause and will use its reasonable best efforts to minimize any resulting delay in or interference with the performance of its obligations hereunder. 5.6. Governing Law; Jurisdiction. This Agreement and all related business transactions will be governed by the laws of the Commonwealth of Massachusetts (without reference to principles of conflicts or choice of law which would cause the application of the internal laws of any other jurisdiction). The courts of or in the Commonwealth of Massachusetts will have nonexclusive jurisdiction over any disputes hereunder. Service of any action or proceeding in any such courts by either party may be made upon the other by registered mail, return receipt requested, at its address given herein. 5.7. Amendments. Neither this Agreement nor any provision hereof may be amended except by a writing duly signed on behalf of each party. 5.8. Remedies. All remedies available to either party for breach of this Agreement are cumulative and may be exercised concurrently or separately. The exercise of one remedy will not be deemed an election of such remedy to the exclusion of other remedies. 5.9. Severability. In the event any provision of this Agreement, in whole or in part, is invalid, unenforceable or in conflict with the applicable laws or 15 -14- regulations of any jurisdiction, such provision will be replaced, to the extent possible, with a provision which accomplishes the original business purposes of the provision in a valid and enforceable manner, and the remainder of this Agreement will remain unaffected and in full force provided, however, that if without such invalid or unenforceable provision the fundamental mutual objectives of the parties cannot be achieved, either party may terminate this Agreement without penalty by written notice to the other. 5.10. Interest. Any overdue amounts payable hereunder will bear interest, payable on demand (whether before or after judgment), from due date to date of payment, at an annual rate of two percent (2%) above the prime rate of Citibank, N.A. in effect on the due date or, if lower, the maximum rate permitted by applicable law. 5.11. Miscellaneous. Each party will bear its own expenses in connection with the negotiation, preparation and execution of this Agreement. The headings of the paragraphs and subparagraphs of this Agreement have been added for the convenience of the parties and are not be deemed a part hereof. This Agreement may be executed in any number of counterparts, all of which together constitute a single agreement. In proving this Agreement, it will not be necessary to produce or account for more than one counterpart signed by the party with respect to which proof is sought. This Agreement is the sole understanding and agreement of the parties with respect to its subject matter and supersedes all other such prior or contemporaneous oral and written agreements and understandings. Signed, sealed and delivered by a duly authorized representative of each party hereto as of the date first written above. THE BUTLER COMPANY BIOPURE CORPORATION By: By: -------------------------------- -------------------------------- Andrew W. Wright, Title: Vice President, Veterinary ----------------------------- Products Address: Address: 11 Hurley Street --------------------------- Cambridge, MA 02141 Telecopy No.: (617) 234-6507 --------------------------- --------------------------- 16 EXHIBIT A BIOPURE CORPORATION Oxyglobin(R) Brand Products Price List (Introductory Promotional Pricing*) Each Box contains two 125 ml bags of Oxyglobin(R) Brand Veterinary Product. Retail Price Retail Price Per
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Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.