KOSMOS ENERGY LTD. Notes to Consolidated Financial Statements (Continued) 3. Acquisitions and Divestitures (Continued) Mauritania. Based on the terms of the agreement, we will reimburse a portion of past and interim period costs and partially carry future costs. In the fourth quarter of 2017, through a joint venture with an affiliate of Trident Energy (‘‘Trident’’), we acquired all of the equity interest of Hess International Petroleum Inc., a subsidiary of Hess Corporation (‘‘Hess’’), which holds an 85% paying interest (80.75% revenue interest) in the Ceiba Field and Okume Complex assets. Under the terms of the agreement, Kosmos and Trident each own 50% of Hess International Petroleum Inc. Hess International Petroleum Inc. was subsequently renamed Kosmos-Trident International Petroleum Inc. (‘‘KTIPI’’). Kosmos is primarily responsible for exploration and subsurface evaluation while Trident is primarily responsible for production operations and optimization. The gross acquisition price was $650 million effective as of January 1, 2017. After post closing entries Kosmos paid net cash of approximately $231 million, with a combination of cash on hand and availability under the Facility. The transaction is accounted for as an equity method investment. In October 2017, we entered into petroleum contracts covering Blocks EG-21, S, and W with the Republic of Equatorial Guinea, subject to ratification by the President of Equatorial Guinea. We presently have an 80% participating interest and are the operator in all three blocks, but pursuant to an agreement with Trident, we expect to assign a 40% participating interest in the blocks to an affiliate of Trident after ratification. The Equatorial Guinean national oil company, Guinea Equatorial De Petroleos (‘‘GEPetrol’’), currently has a 20% carried participating interest during the exploration period. Should a commercial discovery be made, GEPetrol’s 20% carried interest will convert to a 20% participating interest. The petroleum contracts cover approximately 6,000 square kilometers, with a first exploration period of five years from the date of notification of ratification by the President of Equatorial Guinea. The first exploration period consists of two sub-periods of three and two years, respectively. The first exploration sub-period work program includes an approximately 6,000 square kilometer 3D seismic acquisition requirement across the three blocks. Upon ratification and the assignment of a 40% interest to the Trident affiliate noted above, interests in these three blocks will be 40% Kosmos, 40% Trident and 20% GEPetrol. In December 2017, as part of our Alliance with BP, we entered into petroleum contracts covering Blocks CI-526, CI-602, CI-603, CI-707 and CI-708 with the Government of Cote d’Ivoire. We have a 45% participating interest and are the operator in all five blocks. BP has a 45% participating interest in the blocks and the Cote d’Ivoire national oil company, PETROCI Holding (‘‘PETROCI’’), currently has a 10% carried interest. The petroleum contracts cover approximately 17,000 square kilometers, with a first exploration period of three years. The first exploration period work program includes a 12,000 square kilometer 3D seismic acquisition across the five blocks. 2016 Transactions In January and February 2016, we closed farm-in agreements with Equator Exploration Limited (‘‘Equator’’), an affiliate of Oando Energy Resources, for Block 5 and Block 12 offshore Sao Tome and Principe. As a result of subsequent farm-outs we currently have a 45% participating interest and operatorship in each block. The national petroleum agency, ANP STP, has a 15% and 12.5% carried interest in Block 5 and Block 12, respectively. In April 2016, we closed a farm-out agreement with Hess Suriname Exploration Limited, a wholly- owned subsidiary of the Hess Corporation (‘‘Hess’’), covering the Block 42 contract area offshore 120