Inmarsat and SkyWave to Launch New Global Low Data Rate Service

IsatData Pro to Deliver up to 37x Data Capability of Current Global M2M Services

WASHINGTON, DC, March 16, 2011 - Inmarsat (LSE:ISAT), the leading provider of global mobile communications
services, today announced that it is working with partner SkyWave Mobile
Communications to develop a new low data rate tracking, monitoring and
messaging service that is planned for launch in Q3 2011.

IsatData Pro will deliver a significant increase in capability over other
services already in the market. Near real-time messages of up to 10,000 bytes
to the device, and up to 6,400 bytes from the device, will meet the
increasing demand for higher data speeds in machine-to-machine (M2M)
solutions. In comparison, other global M2M services currently on the market
offer data connectivity at just 270-340 bytes.

The new service will support a wide range of security and location-based
services in the fast-growing M2M market: from tracking and in-cab messaging
for commercial transportation and government fleets, transmitting telemetry
information from oil & gas distribution equipment, to remote management and
control of fixed assets.

SkyWave and Inmarsat will promote IsatData Pro to government users and
the road, rail, merchant shipping, commercial fishing, oil & gas, and
utilities sectors. Target geographies include the U.S and Latin America, but
also China and Russia, two rapidly expanding markets for M2M services.

"This is a new service, with new hardware and new infrastructure, that
significantly expands the applications that the Inmarsat system supports,"
said Drew Brandy, Director of Land Services at Inmarsat. "We see lots of
untapped opportunity in the M2M market for a reliable global service that can
offer more: more data, more flexibility and a more reliable network. And, as
people will see when we launch the service, it will be highly cost-effective
too."

The new service was unveiled at the Satellite 2011 Conference and
Exhibition in Washington DC, U.S.

"With IsatData Pro, we are introducing a major innovation into the M2M
market," said David Sward, VP of Marketing and Business Development at
SkyWave. "This will be a global service with a packet data capability far
beyond anything currently out there. Being able to send and receive more data
from remote assets will allow better visibility of business operations and
manage risks more effectively. It enables organisations to stay in touch with
remote assets and workers where, previously, this was technically impossible
or prohibited by cost."

IsatData Pro is ideal for time-critical applications and the very low
latency of messages transmitted means asset owners and managers can exchange
information in near real-time. For example, this will be an advantage for
sending information to drivers operating in high-risk areas, or for receiving
error logs from remote equipment or sensors in an emergency.

The IsatData Pro hardware portfolio manufactured by SkyWave will include
complete terminals for both land and maritime environments, ready for
immediate use on mobile and fixed assets. A modem-only version for OEMs and
systems integrators will also be available.

'IsatData Pro' is an Inmarsat trademark used under licence by SkyWave
Mobile Communications.

About Inmarsat

Inmarsat plc (LSE: ISAT) 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. The company's services are delivered
through a global network of more than 400 distribution partners and service
providers operating in 100 countries. For the year ended 31 December 2010,
Inmarsat plc had total revenue of US$1,171.6 million (2009: US$1,038.1
million) with an EBITDA of US$696.1 million (2009: US$594.2 million). For
more information, please visit www.inmarsat.com.

About SkyWave Mobile Communications

SkyWave Mobile Communications is a global provider of
satellite communication equipment and airtime services for machine-to-machine
(M2M) applications. Using the global Inmarsat satellite constellation, our
products provide dependable communication, tracking, monitoring and remote
management of fixed and mobile assets. Over the past 14 years, we have
designed, manufactured and shipped more than 400,000 satellite terminals to
customers in the transportation, maritime, oil and gas, heavy equipment,
utilities and government sectors. Expand your possibilities with SkyWave.
Visit us at www.skywave.com.

Media Contacts: John Warehand, PR Manager, Inmarsat, Tel: +44(0)20-7728-1579, Mob: +44(0)7739-778-128, Email: john_warehand at inmarsat.com; Anu Sood, Product Marketing Manager, SkyWave Mobile Communications, Tel: +1-613-836-6288 x8320, Mob: +1-613-255-1300, Email: anu.sood at skywave.com