Kosmos Energy Regulatory News (KOS)

GREATER TORTUE AHMEYIM-1 WELL EXPANDS NATURAL GAS RESOURCE POTENTIAL OFFSHORE MAURITANIA AND SENEGAL

DALLAS, Texas, July 1, 2019 - Kosmos Energy (NYSE/LSE: KOS) announced today that the Greater Tortue Ahmeyim-1 well (GTA-1), drilled on the eastern anticline within the unit development area of Greater Tortue, has encountered approximately 30 meters of net gas pay in high-quality Albian reservoir. The Greater Tortue Ahmeyim LNG project is on track to deliver first gas in the first half of 2022, and the well (which has been designed as a future producer) will be used to further optimize the development drilling plans for the BP-operated project.

Commenting on the results of the GTA-1 well, Chairman and Chief Executive Officer Andrew G. Inglis said: "The GTA-1 well confirms our expectation that the gas resource at Greater Tortue Ahmeyim will continue to grow over time and could lead to further expansion of this world-scale 10 MTPA LNG project. In addition, Kosmos' process to sell down its interest to 10 percent has received considerable interest from the industry, with initial bids expected over the summer, and transaction conclusion anticipated by year end."

Located offshore Senegal, the GTA-1 well was drilled in approximately 2,500 meters of water, approximately 10 kilometers inboard of the Guembeul-1A and Tortue-1 wells, to a total depth of 4,884 meters.

The Ensco DS-12 rig, working on behalf of the operator BP, will now drill the Yakaar-2 appraisal well in Senegal, which is expected to spud in the coming weeks, before drilling the Orca-1 exploration well in Mauritania, which is expected to spud late in the third quarter.

Partners in the cross-border Greater Tortue Ahmeyim project, located offshore Mauritania and Senegal, include SMPHM, Petrosen, BP, and Kosmos.

About Kosmos Energy

Kosmos is a full-cycle deepwater independent oil and gas exploration and production company focused on the Atlantic Margins. Our key assets include production offshore Ghana, Equatorial Guinea and U.S. Gulf of Mexico, as well as a world-class gas development offshore Mauritania and Senegal. We also maintain a sustainable exploration program balanced between proven basin infrastructure-led exploration (Equatorial Guinea and U.S. Gulf of Mexico), emerging basins (Mauritania, Senegal and Suriname) and frontier basins (Cote d'Ivoire, Namibia and Sao Tome and Principe). Kosmos is listed on the New York Stock Exchange and London Stock Exchange and is traded under the ticker symbol KOS. As an ethical and transparent company, Kosmos is committed to doing things the right way. The Company's Business Principles articulate our commitment to transparency, ethics, human rights, safety and the environment. Read more about this commitment in the Kosmos 2017 Corporate Responsibility Report. For additional information, visit www.kosmosenergy.com.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. All statements, other than statements of historical facts, included in this press release that address activities, events or developments that Kosmos expects, believes or anticipates will or may occur in the future are forward-looking statements. Kosmos' estimates and forward-looking statements are mainly based on its current expectations and estimates of future events and trends, which affect or may affect its businesses and operations. Although Kosmos believes that these estimates and forward-looking statements are based upon reasonable assumptions, they are subject to several risks and uncertainties and are made in light of information currently available to Kosmos. When used in this press release, the words "anticipate," "believe," "intend," "expect," "plan," "will" or other similar words are intended to identify forward-looking statements. Such statements are subject to a number of assumptions, risks and uncertainties, many of which are beyond the control of Kosmos, which may cause actual results to differ materially from those implied or expressed by the forward-looking statements. Further information on such assumptions, risks and uncertainties is available in Kosmos' Securities and Exchange Commission ("SEC") filings. Kosmos undertakes no obligation and does not intend to update or correct these forward-looking statements to reflect events or circumstances occurring after the date of this press release, except as required by applicable law. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release. All forward-looking statements are qualified in their entirety by this cautionary statement.

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Source: Kosmos Energy Ltd.

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