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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same from the applicable vessel into the navigable waters of the United States, promptly undertake such measures as are reasonably necessary or which may be required by applicable laws, rules and regulations to mitigate the resultant pollution damage; provided, however, that Charterer may at its option, and upon notice to Owner and on the conditions hereinafter set forth, undertake such measures. Charterer shall keep Owner advised of any such measures to be undertaken by it under such circumstances. Any of such measures actually undertaken by Charterer shall be at Owner's expense (except to the extent that such escape or discharge was caused or contributed to by Charterer). If Owner believes that any such measures undertaken by Charterer should not be undertaken or should be discontinued, Owner may so notify Charterer and thereafter Charterer, if it elects to continue such measures, shall do so at its own risk and expense. 4. INDEMNITY. Owner covenants and agrees to fully defend, protect, indemnify and hold harmless Charterer and its affiliates from and against each and every claim, demand, cause of action, liability, damage, cost or expense (including, but not limited to, reasonable attorney's fees and expenses incurred in the defense of Charterer), resulting from any damage to property or injury or death to persons caused, directly or indirectly, by Owner's acts or omissions in connection with Owner's provision of marine transportation services hereunder, except to the extent caused, directly or indirectly, by the acts or omissions of Charterer. Charterer covenants and agrees to fully defend, protect, indemnify and hold harmless Owner and its affiliates from and against each and every claim, demand, cause of action, liability, damage, cost or expense (including, but not limited to, reasonable attorney's fees and expenses incurred in the defense of Owner), resulting from any damage to property or injury or death to persons caused, directly or indirectly, by Charterer's acts or omissions in connection with Charterer's use of marine transportation services hereunder, except to the extent caused, directly or indirectly, by the acts or omissions of Owner. The foregoing indemnities shall expressly exclude any liability for consequential, punitive, special or similar damages, including, without limitation, lost profits. 5. COMPLIANCE WITH LAW; INSURANCE: During the Term of this Agreement, Owner shall comply in all material respects with applicable laws, including, without limitation applicable environmental, health, safety and financial responsibility laws, rules and regulations, applicable to the use of the Vessel for bulk crude oil or finished lubricating products transportation. Owner covenants that it will maintain at all times during the Term of this Agreement insurance coverage for sudden and accidental pollution of $500,000,000. 4 6. CHARTERER'S REPRESENTATIVES: Charterer's representatives may board any vessel used under this Agreement at any convenient place to observe cargo-handling operations, to inspect logs and certificates, and to confirm that Owner is fulfilling its obligations under this Agreement. 7. DRUG & ALCOHOL ABUSE POLICY: Owner warrants that it will maintain and enforce at all times during the Term of this Agreement a drug and alcohol abuse policy applicable to the vessels which complies in all material respects with the minimum standards promulgated by the U.S. Coast Guard. 8. CONDITION OF EQUIPMENT: Owner shall, before and at commencement of each voyage by any vessel under this Agreement, exercise commercially reasonable efforts to ensure that such vessel is seaworthy and in good operating condition, properly manned, equipped and supplied for the voyage, to ensure that the pipes, pumps and coils tight, staunch, are in good operating condition and fit for the voyage, and to ensure that the tanks and other spaces in which product is to be carried are in good operating condition and fit for the carriage and preservation of the same. To the extent required by applicable law, Owner will maintain at all times during the Term of this Agreement a valid and subsisting certificate or other permit issued by the U.S. Coast Guard (or other governmental bureau or department having jurisdiction) approving the applicable vessel for the transportation and carriage of inflammable liquids. 9. SUBLET: Charterer shall not be permitted to sublet the use of any vessels to any third party. 10. FORCE MAJEURE: The vessels, their captains and Owner shall not, unless otherwise in this Agreement expressly provided, be responsible for any loss or damage arising or resulting from: any act, default or barratry of the captain, pilots, mariners, or other servants of Owner in the navigation or management of such vessel; fire, unless caused by the personal design or neglect of Owner;
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Extract the exact clause related to "Anti-Assignment" from the excerpt above.

assistant: Charterer shall not be permitted to sublet the use of any vessels to any third party.