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               22 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       9,087,473      1.98%      533,275       0.12%
securities
(2) Derivatives      556,303      0.12%    2,513,135       0.55%
(other than
options)
(3) Options and            0      0.00%            0       0.00%
agreements to
purchase/sell
Total              9,643,776      2.10%    3,046,410       0.66%

(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      39,169               4.6627
Purchase      8,263                4.6821
Purchase      11,298               4.6502
Purchase      8,230                4.6915
Purchase      93,583               4.6647
Purchase      1,467                4.6875
Purchase      2,424                4.6250
Purchase      2,926                4.6745
Purchase      178,270              4.6640
Sale          19,500               4.6546
Sale          63,753               4.6615
Sale          34,683               4.6616
Sale          19,299               4.6645
Sale          58,785               4.6840
Sale          3,204                4.6947
Sale          5,230                4.6718
Sale          178,270              4.6640
Sale          2,800                4.6350
Sale          2,926                4.7192

(b)  Derivatives transactions (other than options)
Product name,  Long/Short    Number of     Price per
(e.g. CFD)     (Note 6)      Securities    unit (GBP)
CFD            Long          2800          4.635
CFD            Long          63753         4.6614
CFD            Long          34683         4.6615
CFD            Long          178270        4.6639
CFD            Long          19299         4.6644
CFD            Long          73778         4.6663
CFD            Long          5230          4.6717
CFD            Long          58785         4.6839
CFD            Long          2926          4.7192
CFD            Short         2424          4.625
CFD            Short         11298         4.6502
CFD            Short         39169         4.6626
CFD            Short         178270        4.6639
CFD            Short         93583         4.6647
CFD            Short         2926          4.6745
CFD            Short         8263          4.682
CFD            Short         1467          4.6874
CFD            Short         9810          4.6889
CFD            Short         8230          4.6914
CFD            Short         17820         4.6933

(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                         23 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