Deed of Novation and Amendment dated September 20, 2017 between Tullow Mauritania Limited, Total E&P Mauritania Block C18 B.V., Kosmos Energy Mauritania, BP Mauritania Investments Limited and SMHPM in related to Block C-18

TULLOW MAURITANIA LIMITED, a company incorporated under the laws of the Isle of Man (Previous Registration No. 104570C and Current Registration No. 010509V) whose registered office is at Falcon Cliff, Palace Road, Douglas, Isle of Man, IM2 4LB (the “Assignor”);

TOTAL E&P MAURITANIA BLOCK C18 B.V. a company incorporated under the laws of the Netherlands and having its registered office at Bordewijklaan 18, 2591 XR The Hague, The Netherlands (“Assignee”);

KOSMOS ENERGY MAURITANIA, a company incorporated in the Cayman Islands whose registered office is at c/o Circumference (Cayman), P.O. Box 32322, 4th Floor, Century yard, Cricket Square, Hutchins Drive, Elgin Avenue, George Town, Grand Cayman, KY1-1209, Cayman Islands (the "Kosmos");

BP MAURITANIA INVESTMENTS LIMITED, a company incorporated in England and Wales whose registered office is at Chertsey Road, Sunbury on Thames, Middlesex TW16 7BP, United Kingdom (“BP”); and

SOCIÉTÉ MAURITANIENNE DES HYDROCARBURES ET DE PATRIMOINE MINIER (previously named Société Mauritanienne des Hydrocarbures (SMH)), the national oil company of Mauritania, incorporated by Decree No.2005 -106 dated 7 November 2005 as abrogated by and replaced with Decree No. 2009-168 dated 3 May 2009 amended by Decree No. 2014-001 dated 06 January 2014 under the laws of the Islamic Republic of Mauritania and having its registered office at Ilot K, Rue 42-133, No. 349, B.P. 4344, Nouakchott, Islamic Republic of Mauritania (“SMHPM” ).

The Assignor entered a contract for the exploration and production of Hydrocarbons in block C-18 offshore Mauritania, dated 17 May 2012 and with an effective date of 15 June 2012, with the Islamic Republic of Mauritania, as represented by the Minister in charge of Petroleum, Energy and Mines (the “Contract”) and pursuant to article 21 of the Contract the Government, through SMHPM, acquired as at the effective date of the Contract a Participating Interest of ten percent (10%).

The Assignor, Kosmos, BP and SMHPM are parties to a Joint Operating Agreement dated 11 September 2012 related to block C-18 offshore Mauritania (the “JOA”) as amended by a deed of novation and amendment signed by the Assignor, Kosmos, BP and SMHPM dated 24 August 2017 (“Kosmos/BP Deed of Novation”).

By the Sale and Purchase Agreement dated 20 April 2017, the Assignor has agreed to assign and transfer to the Assignee an undivided forty-five percent (45%) Participating Interest in the Contract and the JOA (the “Transfer”).

The Minister of Petroleum, Energy and Mines by letter n° 00000742/M.P.E.M./MM dated 9 August 2017 has approved the Transfer contemplated by the SPA; and

It is a requirement of the JOA that this Deed be executed to effect the assignment and transfer of the Assigned Interest under the Transfer.

has by this Deed become a party to the JOA in lieu of the Assignor to the extent of the Assigned Interest;

is entitled to all of the rights and benefits of the Assignor under the Contract and the JOA to the extent of the Assigned Interest in lieu of the Assignor; and

by this Deed, undertakes and covenants with the Assignor, Kosmos, BP and SMHPM to observe and perform the Assignor’s Covenants with respect to the Assigned Interest.

remains liable to Kosmos, BP, SMHPM and the Assignee under the Transfer for, and must observe and perform, all the Assignor's Covenants arising in respect of Joint Operations carried out under the JOA before the Assignment Date with respect to the Assigned Interest; and

arising, in respect of Joint Operations carried out under the JOA, before the Assignment Date to the extent of the Assigned Interest.

The Participants confirm that this Deed is intended to fully comply with the JOA. In case of inconsistency between the provisions of this Deed and the provisions of the JOA (except for the amendments to the JOA stated in Clauses 4, 5, 7 and 8 of this Deed), the provisions of the JOA prevail.

SMHPM, Kosmos and BP’s consent to the assignment, transfer and novation under the Transfer is evidenced by this Deed when it becomes in full force pursuant to Clause 9.1.

On and from the Assignment Date, the Assignee will become a Party to the JOA and the Participating Interests of the Parties under Article 3.2(A) of the JOA:

on and from the Assignment Date to 31 May 2017 at 24:00 hours (London time) shall be:

and, on and from the Kosmos/BP Assignment Date, shall be:

At Article 3.4(E) of the JOA in the second paragraph beginning “For the avoidance of doubt…” the table shall be deleted and replaced with the following:

on and from the Assignment Date to 31 May 2017 at 24:00 hours (London time):

and, on and from the Kosmos/BP Assignment Date:

With effect from the Completion Date, Article 18.3 of the JOA is amended as follows:

Each Participant acknowledges and agrees that notwithstanding that the Assignment Date precedes the Kosmos/BP Assignment Date:

the transfers of Participating Interests to BP and Kosmos pursuant to the Kosmos/BP Deed of Novation were validly made and, as at the date of this Deed, BP and Kosmos each legitimately holds a 15% Participating Interest;

each Participant hereby waives any right it may otherwise have (including, without limitation, any right that the Assignee, Assignor or SMHPM may have or claim to have pursuant to the JOA or SPA or other agreement) to challenge the validity or effectiveness of such transfers of Participating Interest to BP and Kosmos; and

the amendments to the JOA made pursuant to the Kosmos/BP Deed of Novation were validly made and are fully binding on all Participants.

For the purposes of Article 17 of the JOA, the address of the Assignee for delivery or transmission of notices is:

This Deed is of no force until the Assignor and the Assignee have formally notified Kosmos, BP and SMHPM of the occurrence of the completion under the SPA and of the Completion Date.

Each Participant, as applicable, must use all reasonable efforts, execute all documents and do all acts and things necessary or desirable to enable all matters contemplated by this Deed to be approved by the Government (if necessary) as quickly as possible.

From the date this Deed comes into force pursuant to Clause 9.1, the transfer and assignment of the Assigned Interest under the Transfer will relate back and be deemed to have occurred on the Assignment Date.