Inmarsat plc Reports Interim Results 2010

LONDON, August 6, 2010 - Inmarsat plc (LSE: ISAT), the leading provider of global
mobile satellite communications services, today reported consolidated
financial results for the 6 months ended 30 June 2010.

Inmarsat plc Interim Results Highlights

    - Total revenue $570.7m up 12.2% (2009: $508.7m)

    - Inmarsat Global MSS revenue $362.9m up 9.4% (2009: $331.6m)

    - EBITDA $334.4m up 15.4% (2009: $289.9m)

    - Profit before tax $151.8m up 56% (2009: $97.0m)

    - Interim dividend of 14.00 cents (US$) up 10%

    - Inmarsat-5: new satellite investment announced today

    - Global handheld satellite phone launched on schedule in June

    - New 5-year Inmarsat MSS revenue growth target provided

Inmarsat Group Limited Second Quarter Highlights

    - Total revenue $289.2m up 12.6% (2009: $256.9m)

    - EBITDA $168.6m up 13.8% (2009: $148.2m)

    - Stratos refinancing and reorganisation completed

Andrew Sukawaty, Inmarsat's Chairman and Chief Executive
Officer, said, "Our first half performance continues to show the profitable
growth in the markets we serve and we are well-positioned to deliver our
growth objectives for the year. In June, we successfully launched our global
handheld satellite phone as planned. The announcement today of our investment
in the new Inmarsat-5 constellation positions us to expand our leadership in
the global MSS industry. Both of these developments demonstrate our strategy
of investing for growth in the markets we serve best."

Rick Medlock, Chief Financial Officer, added. "The continued
growth in both our cash flow and profitability strongly support the 10%
increase in dividend announced today. Taking into account our new capital
investment plans and the anticipated performance of our existing business, we
are confident that our dividend growth can be sustained at the current rate
for the next three years."

Inmarsat plc Revenue

                                                 Six months ended  Increase
                                                      30 June         %
    (US$ in millions)                             2010      2009

    Inmarsat Global                              367.8     336.6      9.3%
    Stratos                                      355.8     317.2     12.2%
                                                 723.6     653.8     10.7%
    Intercompany eliminations and adjustments   (152.9)   (145.1)
    Total revenue                                570.7     508.7     12.2%

Inmarsat Global

    Revenue                                     Six months ended    Increase/
                                                    30 June        (decrease)
                                                  2010      2009       %
    (US$ in millions)                                 

    Maritime sector
     Voice services                               48.9      53.1      (7.9%)
     Data services                               128.8     123.6       4.2%
     Total maritime sector                       177.7     176.7       0.6%
    Land mobile sector
     Voice services                                4.0       4.7     (14.9%)
     Data services                                75.8      65.3      16.1%
     Total land mobile sector                     79.8      70.0      14.0%
    Aeronautical sector                           49.6      35.5      39.7%
    Leasing                                       55.8      49.4      13.0%
    Total mobile satellite communications
    services                                     362.9     331.6       9.4%
    Other income                                   4.9       5.0      (2.0%)
    Total revenue                                367.8     336.6       9.3%

During the first half our maritime revenue growth was impacted
by the challenging economic climate in shipping. However, new additions of
Fleet and FleetBroadband terminals have remained strong throughout the period
and provide a positive forward indicator of demand for our maritime services.
In addition, during the second quarter, we saw some improving trends in our
maritime data business and we remain optimistic for improved maritime
performance in the second half of the year.

Our land mobile sector revenue growth was driven by demand for
our BGAN service and was boosted by additional BGAN demand in response to the
earthquake events in Haiti and Chile in the first quarter. During the second
quarter, we experienced a slowdown in BGAN demand in connection with lower
usage levels in Afghanistan. Usage of our BGAN service in Iraq and
Afghanistan has historically been volatile and resulted in fluctuations in
revenue growth from time to time.

Strong aeronautical revenue growth was driven by particularly
high levels of usage of our Swift 64 service. New additions of SwiftBroadband
terminals remained strong throughout the first half and now far outstrip
new additions of Swift 64 terminals, demonstrating market acceptance of this
important service. Our leasing business growth was driven by new leasing
business across our business sectors.

Stratos

    Revenue                                    Six months ended
                                                   30 June      Increase
                                                2010     2009      %
    (US$ in millions)                                

    MSS revenue
     Inmarsat MSS                               215.1   208.0     3.4%
     Other MSS                                   64.0    62.3     2.7%
    Total MSS revenue                           279.1   270.3     3.3%
     Broadband (including Segovia)               76.7    46.9    63.5%
    Total revenue                               355.8   317.2    12.2%

In January 2010 we completed the acquisition of Segovia, a
provider of managed communications solutions principally to US government
agencies, and report revenue from this business within our Stratos segment.
Revenue growth in our Stratos Broadband business predominately resulted from
the newly recognised Segovia revenue.

Outlook

As a result of our business performance in the first half and
the successful launch of our handheld global satellite phone service, we
remain on track to deliver solid revenue growth in 2010. We are also
announcing a target average annual revenue growth rate for our Inmarsat
Global MSS revenues of 5-7% for the period 2010 - 2014 (using the revenue for
2009 as the base year).

Following the separate announcement today of our Inmarsat-5
investment programme, we are revising our capital expenditure guidance to
$240 - 250m for 2010. This includes capital expenditure for our existing
operations, which remains unchanged at $160 - 170m.

Taking into account our new capital investment plans and the
anticipated performance of our existing business, we are confident that our
rate of dividend growth can be sustained at 10% for the next three years
(2010-2012).

Liquidity

At 30 June 2010, the Inmarsat plc group had net borrowings of
$1,346.1m, made up of cash and cash equivalents of $141.8m and total
borrowings of $1,487.9m. Taking into consideration our cash on hand and
available but undrawn borrowing facilities of $272.9m, the group had total
available liquidity at 30 June 2010 of $414.7m. During the first half, we
used available liquidity to repay and cancel our Stratos Senior Credit
Facility of $207.0m and to fully redeem our Stratos Senior Unsecured Notes of
$62.4m. In connection with these debt repayments we recorded non-recurring
interest items of $8.9m during the first half.

Our Financial Reports

In addition to the interim results reported for Inmarsat plc,
Inmarsat Group Limited, our wholly-owned subsidiary, today also reported
unaudited consolidated financial results for the 3 months ended 30 June 2010.
Following the completion of a reorganisation plan during the second quarter,
the companies comprising our Stratos business became indirect wholly-owned
subsidiaries of Inmarsat Group Limited. In line with accounting principles,
we have re-presented the 2009 year and presented the 2010 year for Inmarsat
Group Limited to reflect the operational results of Stratos as if Stratos had
been owned for the entire period. A copy of the full financial report for
Inmarsat Group Limited can be accessed via the investor relations section of
our website.

Other Information

Inmarsat management will host a presentation of the interim
results and other financial and business information on Friday, 6 August at
9:30 a.m. London time. The presentation will take place at our offices at 99
City Road, London EC1Y 1AX. The meeting and presentation will also be
available via a live webcast and available for replay after the event, to
access the webcast please go to www.inmarsat.com/webcast.

Forward-looking Statements

Certain statements in this announcement constitute
"forward-looking statements" within the meaning of the U.S. Private
Securities Litigation Reform Act of 1995. These forward-looking statements
involve risks, uncertainties and other factors that may cause our actual
results, performance or achievements, or industry results, to be materially
different from those projected in the forward-looking statements. These
factors include: general economic and business conditions; changes in
technology; timing or delay in signing, commencement, implementation and
performance of programmes, or the delivery of products or services under
them; structural change in the satellite industry; relationships with
customers; competition; and ability to attract personnel. You are cautioned
not to rely on these forward-looking statements, which speak only as of the
date of this announcement. We undertake no obligation to update or revise any
forward-looking statement to reflect any change in our expectations or any
change in events, conditions or circumstances.

Contact: Inmarsat, London, UK, Investor Enquiries, Simon Ailes, Tel: +44-(0)20-7728-1518, simon_ailes at inmarsat.com; Media Enquiries, Chris McLaughlin, Tel: +44-(0)20-7728-1015, christopher_mclaughlin at inmarsat.com