Rule 8.3 - INMARSAT

FORM 8.3

    DEALINGS BY PERSONS WITH INTERESTS IN SECURITIES REPRESENTING 1% OR MORE
              (Rule 8.3 of the City Code on Takeovers and Mergers)


1.   KEY INFORMATION

Name of person dealing        BARCLAYS PLC
(Note 1)
Company dealt in              INMARSAT
Class of relevant security    ORD EUR0.0005
to which the dealings being
disclosed relate (Note 2)
Date of dealing               09 July 2008

2.   INTERESTS, SHORT POSITIONS AND RIGHTS TO SUBSCRIBE

(a)  Interests and short positions (following dealing) in the class of relevant
security dealt in (Note 3)

                            Long                     Short

                      Number       (%)         Number       (%)

(1) Relevant       9,311,263      2.03%      513,528       0.11%
securities
(2) Derivatives      610,161      0.13%    2,584,878       0.56%
(other than
options)
(3) Options and            0      0.00%            0       0.00%
agreements to
purchase/sell
Total              9,921,424      2.16%    3,098,406       0.68%


(b)  Interests and short positions in relevant securities of the company, other
     than the class dealt in (Note 3)

Class of                    Long                     Short
relevant
security:

                  Number              (%)   Number              (%)

(1) Relevant
securities

(2) Derivatives
(other than
options)

(3) Options and
agreements to
purchase/sell

Total


  (c)  Rights to subscribe (Note 3)

Class of relevant security:   Details



3.   DEALINGS (Note 4)

  (a)  Purchases and sales

Purchase/sale Number of Securities Price per unit
                                   (GBP)
Purchase      17,240               5.0666
Purchase      33,845               5.0590
Purchase      65,000               5.0350
Purchase      14,652               5.0640
Purchase      42,404               5.0559
Purchase      27,057               5.0553
Purchase      1,629                5.0908
Purchase      9,296                5.0483
Sale          19,800               5.0669
Sale          65,000               5.0350
Sale          13,773               5.0512
Sale          23,588               5.0544
Sale          37,506               5.0650
Sale          39,190               5.0567
Sale          410                  5.0392
Sale          2,800                5.0450
Sale          5,600                5.0450

(b)  Derivatives transactions (other than options)
Product name,  Long/Short    Number of     Price per
(e.g. CFD)     (Note 6)      Securities    unit (GBP)
CFD            Long          410           5.0391
CFD            Long          8400          5.045
CFD            Long          13773         5.0512
CFD            Long          23588         5.0543
CFD            Long          3779          5.0547
CFD            Long          39190         5.0567
CFD            Long          37506         5.0649
CFD            Long          19800         5.0668
CFD            Short         4713          5.034
CFD            Short         9296          5.0483
CFD            Short         14165         5.0511
CFD            Short         27057         5.0553
CFD            Short         42404         5.0558
CFD            Short         33845         5.059
CFD            Short         14652         5.0639
CFD            Short         17240         5.0665
CFD            Short         1629          5.0908

(c)  Options transactions in respect of existing securities

(i)  Writing, selling, purchasing or varying

Product name,   Writing,          Number of          Exercise  Type, e.g.      Expiry   Option money
e.g. call       selling,          securities to      price     American,       date     paid/received
option          purchasing,       which the option             European etc.            per unit (GBP)
                varying etc.      relates (GBP)


(ii) Exercising

Product name, e.g.  Number of           Exercise price per
call option         securities          unit (Note 5)




(d)  Other dealings (including new securities) (Note 4)


Nature of transaction Details           Price per unit
(Note 8)                                (if applicable)
                                        (Note 5)




4.   OTHER INFORMATION
None

Agreements, arrangements or understandings relating to options or derivatives


Full details of any agreement, arrangement or understanding between the
person disclosing and any other person relating to the voting rights of
any relevant securities under any option referred to on this form or
relating to the voting rights or future acquisition or disposal of any
relevant securities to which any derivative referred to on this form is
referenced.  If none, this should be stated.




Is a Supplemental Form 8 attached? (Note 9)                 NO


Date of disclosure                         10 July 2008
Contact name                               Geoff Smith
Telephone number                           020 7116 2913
If a connected EFM, name of
offeree/offeror with which connected
If a connected EFM, state nature of
connection (Note 10)


Notes

The Notes on Form 8.3 can be viewed on the Takeover Panel's website at
www.thetakeoverpanel.org.uk