Kosmos Energy Regulatory News (KOS)

NEWS RELEASE

YAKAAR-2 APPRAISAL WELL CONFIRMSWORLD-SCALE GAS RESOURCE OFFSHORE SENEGAL

DALLAS, Texas, September 23, 2019 - Kosmos Energy (NYSE/LSE: KOS) announced today that the Yakaar-2 appraisal well has encountered approximately 30 meters of net gas pay in similar high-quality Cenomanian reservoir to the Yakaar-1 exploration well, continuing the 100 percent success rate of wells targeting the inboard Mauritania/Senegal gas trend. Yakaar-2 was drilled approximately nine kilometers from Yakaar-1 and proved up the southern extension of the field.

The results of the Yakaar-2 well underpin our view that the Yakaar-Teranga resource base is world-scale and has the potential to support an LNG project that provides significant volumes of natural gas to both domestic and export markets. Development of Yakaar-Teranga is expected in a phased approach with Phase 1 providing domestic gas and data to optimize the development of future phases. It will also support the country's "Plan Emergent Senegal" launched by the President of Senegal in 2014.

Commenting on the results of the Yakaar-2 well, Chairman and Chief Executive Officer Andrew G. Inglis said: "The Yakaar-2 appraisal well demonstrates the scale and quality of the Yakaar resource base. Senegal is one of the fastest growing economies in the world and Kosmos is excited to be working alongside BP and PETROSEN to support the country's growing energy needs."

Located offshore Senegal, the Yakaar-2 well was drilled in approximately 2,500 meters of water to a total measured depth of around 4,800 meters.

The Valaris DS-12 rig, working on behalf of the operator BP, will now move to the Orca-1 exploration well in Mauritania.

Partners in the Yakaar-Teranga gas project, located offshore Senegal, include 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 2018 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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