Commercial Service Introduction for Global Xpress

Inmarsat confirms global commercial service introduction (CSI) for Global Xpress constellation

London, UK: 4 January 2016. Inmarsat plc (LSE: ISAT.L), the leading provider of global mobile satellite communications services, today confirmed that global Commercial Service Introduction (CSI) was achieved during December 2015 for its new Global Xpress (GX) constellation, which is formed of three Ka-band, high-speed mobile broadband communications satellites.

A fourth GX satellite - Inmarsat-5 F4 - is currently completing construction and testing by Boeing in California. This satellite is now likely to be launched in the second of half 2016 in order to provide additional GX network capacity.

During the course of 2016, Inmarsat will be introducing a series of market-specific, high-speed connectivity services powered by Global Xpress.

Further information:

Investors Media

Morten Singleton 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 employs around 1,600 staff in more than 60 locations 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 (LSE: ISAT.L). For more information, please visit http://www.inmarsat.com/

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