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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EXHIBIT 10.6 TRANSPORTATION CONTRACT SPECIFIC CONDITIONS PURPOSE ECONOMIC CONDITIONS CONTRACTED CAPACITY POINTS OF ENTRANCE AND EXIT MANSOYÁ - TUMACO Date Bogota D.C. January 30, 2012 Contract No. VIT-005-2012 SENDER SOLANA PETROLEUM EXPLORATION COLOMBIA LIMITED TAX ID 830.051.027-8 SHIPPER ECOPETROL S.A. TAX ID 899.999.068-1 T Y P E O F CRUDE OWN PRODUCTION x PROPERTY Transportation Service of liquid hydrocarbons through the "Trasandino" Pipeline(OTA) and Mansoyá-Orito (OMO) pipeline. Estimated Value of the Contract Six millions seven hundred forty five thousand dollars of The United States of America (USD$6.745.000). Rate "Mansoyá-Orito" Pipeline (OMO) Cero point five one nine two dollars of The Untied States of America (USD$0,5192) per Barrel Rate "Trasandino" Pipeline (OTA) Three dollars eleven forty three cents of dollars of The Untied States of America (USD$3,1143) per Barrel. PRODUCT Daily Average (Barrels/calendar day) Monthly average (Barrels/month) Crude 10.000 300.000 TERM OF EXECUTION From January 30, 2012 until July 29, 2012 Point # Type of Point Name of Point Distance (km) 1 Point of Entrance Entrance bridle to the srapers tramp in the PK 35+400 of OMO 377,3 2 Point of Exit Exit bridle to the main tanks of Tumaco Plant. SPECIFICATIONS OF PRODUCTS TO BE SHIPPED PRODUCT CHARACTERISTICS Quality Specifications of Crude: Bases on the operating conditions of the "Trasandino" Pipeline, ECOPETROL shall only receive daily crude oil from the SENDER up to a maximum equivalent to 12% of the total light crude received in the day at the Orito Plant. The indicated Quality Specifications correspond to those which the final mix of crude delivered by the SENDER shall have. In the event in which the Crude delivered by the SENDER fails to meet the Quality Specification and if the buying of dissolvent is required to make mixes, the SENDER shall request approval from ECOPETROL before its delivery for transportation by ECOPETROL. It is the SENDER's responsibility to ensure its possession, control and entitlement to deliver or make deliver on its behalf the crude received by ECOPETROL at the Entrance Point. The SENDER shall hold ECOPETROL harmless against any claim, action or damages which may result from suits, claims or administrative, judicial or extrajudicial actions from any third persons alleging ownership or possession on the crude to be shipped. BONDS In witness whereof, and accepting the General Conditions and the Specific Conditions this Contract is subscribed in two (2) duplicates of the same content in the city of Bogotá on the thirtieth (30th) day of the month of January, 2012. Characteristics Lower Limit Upper Limit Temperature 120°F Viscosity 300 cSt 30ºC. Water and sediments (BSW) 0,5 % in volume Salt 20 PTB Steam pressure Eleven (11) psi at 100°F Gravity in API degrees 18 degrees 50 degrees TYPE OF BOND AMOUNT Performance Insurance Policy Four thousand forty seven millions of Colombian pesos ($4.047.000.000) 1 All notifications and communications to be delivered to the Parties as a result of the execution of the Contract hereof shall be made to the addresses indicated as follows: ECOPETROL THE SENDER BY THE SENDER: BY ECOPETROL S.A.: Signature "/s/ Duncan Nightingale" Signature "/s/ Rafael Espinosa Rozo" Name: DUNCAN NIGHTINGALE Name: RAFAEL ESPINOSA ROZO Title: Legal Representative Pasaporte No. BA386341 Title: Pipelines Manager C.C. No. 79.432.773 de Bogotá D.C. Signature "/s/ Hugo Rodriguez" Name: HUGO RODRIGUEZ Title: Legal Representative C.C. No. 3.093.980 ADDRESS 5.1 Carrera 7 No. 37 - 69 Piso 9 Edificio Teusacá TELEPHONE 5.2 2343491 FAX 5.3 2343532 CITY 5.4 Bogotá D.C. ADDRESS 5.5 Calle 113 No. 7 - 80 Piso 17 TELEPHONE 5.6 6585757 FAX 5.7 2139327 CITY 5.8 Bogotá D.C. 2 TRANSPORTATION CONTRACT GENERAL CONDITIONS The Contract hereof executed between ECOPETROL and the SENDER shall be comprised by these General Clauses and by the Specific Conditions subscribed by the Parties. All current legal provisions shall apply thereto and therefore the Parties are obliged to fulfill them regardless of whether or not they are stated in this document or in the Specific Conditions. PARTIES: The Parties of the Contract shall be: ECOPETROL S A, hereinafter ECOPETROL, a company of mixed economy, authorized by law 1118 of 2006, attached to the Ministry of Mines and Energy, acting pursuant to its by-laws with its main domicile in Bogotá D C with Tax ID 899.999.068- 1, represented by whoever subscribes the Specific Conditions of the Contract and the SENDER, identified as indicated in the Specific Conditions, who is obliged subject to the conditions and terms set forth herein. ECOPETROL and the SENDER may also be called in this Shipment Contract or "Contract", individually as the "Party"
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Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.