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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accordance with law. 23.8 ECOPETROL may request the return of the Information at any time after notifying in writing to the other Party. Within thirty (30) days following the reception of said notification, the SENDER shall return all original Information and destroy or make to be destroyed all copies and reproductions (in any manner, including but without being limited to electronic means) in its possession and in possession of persons to whom it was disclosed pursuant with the Contract hereof. In any case, upon expiration of the term of execution of the Contract, the SENDER shall return all original Information and destroy or make to be destroyed all copies and reproductions (in any manner, including but without being limited to electronic means) in its possession and in possession of persons to whom it was disclosed pursuant with the Contract hereof. 23.9 During the term of execution of the Contract, ECOPETROL is obliged to keep in reserve and not to disclose the information expressly identified and in writing by the SENDER that is protected by copyrights or industrial secret pursuant to the regulations in force, that is directly delivered by the SENDER as a result of the execution of the Contract, and makes the commitment not to deliver said information to any third parties, except as ordered by the judicial or administrative authorities or in events required by the legal provisions in force. 23.10 This confidentiality clause shall keep its validity, inclusively after the date of termination of the Contract hereto, until the date in which all obligations set out in this clause are fulfilled. 13 CLAUSE TWENTY-FOURTH SOCIAL CORPORATE RESPONSIBILITY 24.1 The SENDER undertakes the commitment to: a) Respect and obey the Good Governance Code and Policies of Integral Responsibility and Social Corporate Responsibility of ECOPETROL. b) Make the best efforts to establish and maintain, as best as possible, good relations with the institutions (authorities) and communities settled in the region and in the area where the Contract shall be executed. c) Report to ECOPETROL or whoever replaces it, any incidents or new actions that may affect its image and/or the image of ECOPETROL, within three (3) business days after the occurrence of said incidents, in order to have consensus in the handling of said incidents. CLAUSE TWENTY-FIFTH COMMITMENT WITH TRANSPARENCY 25.1 The SENDER undertakes the obligation to: 25.2 The SENDER states to be aware of and accepts the Code of Ethics of ECOPETROL found in the following website: www.ecopetrol.com.co, and the provisions on conflict of interest existing in the by-laws of ECOPETROL found in the same website. In case ECOPETROL determines that the SENDER has incurred in conducts that violate the clause hereof, ECOPETROL may terminate the Contract. a) Maintain conducts and appropriate controls to ensure an ethical conduct and in accordance with regulations in force. b) Refrain from making (directly or indirectly, or through employees, representatives, affiliates or contractors) payments, loans, gifts, gratifications, commissions, to employees, managers, administrators, contractors or suppliers of ECOPETROL, public officials, members of corporations of popular election or political parties, in order to induce such persons to conduct any action or make any decision or use their influence in order to contribute to obtain or retain businesses in connection with the Contract. c) Refrain from originating records or inaccurate information, or publish information that affects the image of the other Party when based on assumptions that have not been demonstrated. d) Avoid any situation which may generate a conflict of interest. e) Communicate mutually and reciprocally any deviation from the line of conduct indicated in this clause. 14 CLAUSE TWENTY-SIXTH INTEGRITY 26.1 The Contract hereof constitutes a sole and integral agreement regarding the purpose of the same and replaces any previous agreement that has not been written in this Contract. 26.2 The following documents are an integral part of the Contract: 26.3 Likewise, all regulations and procedures that ECOPETROL has established for the development of the activities being the purpose hereto are an integral part of this Contract. CLAUSE TWENTY-SEVENTH LEGAL REGIME 27.1 The relation established in the Contract hereof is of commercial nature and therefore is governed by the regulations of Colombian private law. CLAUSE TWENTY-EIGHTH NOTIFICATIONS 28.1 All communications and invoices between the SENDER and ECOPETROL delivered as a result of this Contract shall require for its validity to be in writing, and depending on the will of the Party issuing it, they will have to be: 28.2 All communications shall deemed as served and valid: ANNEX 1 MANUAL OF THE SHIPPER
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Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.