Inmarsat Govt chosen by AT&T for major US network

Inmarsat Government selected by AT&T as a core team member for the U.S. FirstNet network

31 March 2017: Inmarsat Government, a wholly-owned subsidiary of Inmarsat plc (LON: ISAT), has been selected by AT&T (NYSE: T) as a core team member for the U.S. FirstNet network.

Inmarsat Government will work with AT&T to deliver satellite communication solutions as part of the FirstNet network.

The First Responder Network Authority (FirstNet) is an independent agency under the U.S. Department of Commerce. Its public safety mission is to build, operate and maintain the first U.S. high-speed, nationwide wireless broadband network dedicated to police, firefighters and emergency medical services.

For further details, please visit the AT&T website at: http://about.att.com/story/firstnet_selects_att_to_build_network_supporting_first_responders.html

ENDS

Contacts:

Investor Enquiries: Media Enquiries:

Rob Gurner Jonathan Sinnatt

Tel: +44 (0)20 7728 1518 Tel: +44 (0)20 7728 1935

[email protected] [email protected]

About Inmarsat

Inmarsat plc is the leading provider of global mobile satellite communications services. Since 1979, Inmarsat has been providing reliable voice and high-speed data communications to governments, enterprises and other organizations, with a range of services that can be used on land, at sea or in the air. Inmarsat operates around the world, with a presence in the major ports and centres of commerce on every continent. Inmarsat is listed on the London Stock Exchange (ISAT.L). For more information, please visit www.inmarsat.com.

About Inmarsat Government

Inmarsat Government is the leading provider of secure, reliable and affordable mission-critical telecommunications to U.S. military, intelligence and civilian organizations. Equipped with the industry's leading satellite and terrestrial infrastructure, it delivers custom, end-to-end networks and solutions that can sustain communications anytime, anywhere. Inmarsat Government, a wholly-owned subsidiary of Inmarsat plc, and an authorized Value Added Reseller (VAR) for Inmarsat Global Xpress, is responsible for Inmarsat's retail U.S. government business. It is headquartered in Reston, VA, with network assets and operations around the globe. For more information, please visit www.inmarsatgov.com.