Inmarsat plc is a British satellite telecommunications company, offering global mobile services. It provides telephone and data services to users worldwide, via portable or mobile terminals which communicate to ground stations through eleven geostationary telecommunications satellites.

Inmarsat's analysis of satellite data in March 2014 showed that Malaysia Airlines Flight 370 flew south from its last known position north of its originating airport in Kuala Lumpur -- rather than continuing to fly north, as it was supposed to. That analysis was the key factor in causing the search area for the missing plane to be shifted from its last known position to the southern Indian Ocean.