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               17 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       9,253,099      2.02%      495,718       0.11%
securities
(2) Derivatives      571,950      0.12%    2,803,048       0.61%
(other than
options)
(3) Options and            0      0.00%            0       0.00%
agreements to
purchase/sell
Total              9,825,049      2.14%    3,298,766       0.72%


(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      3,267                4.9325
Purchase      6,845                4.9297
Purchase      7,735                4.9198
Purchase      3,422                4.9219
Purchase      23,402               4.9097
Purchase      10,060               4.9333
Purchase      4,926                4.9212
Sale          12,660               4.9135
Sale          1,035                4.9600
Sale          3,422                4.9467
Sale          28,007               4.9205
Sale          2,070                4.9600
Sale          277                  4.9592
Sale          2,108                4.9260
Sale          24,402               4.9390
Sale          10,000               4.9345
Sale          13,532               4.9319
Sale          8,095                4.9214
Sale          2,420                4.9625

(b)  Derivatives transactions (other than options)
Product name,  Long/Short    Number of     Price per
(e.g. CFD)     (Note 6)      Securities    unit (GBP)
CFD            Long          12660         4.9134
CFD            Long          28007         4.9204
CFD            Long          2108          4.926
CFD            Long          13532         4.9318
CFD            Long          10000         4.9345
CFD            Long          24402         4.939
CFD            Long          3422          4.9467
CFD            Long          277           4.9592
CFD            Long          2420          4.9625
CFD            Short         23402         4.9097
CFD            Short         7735          4.9197
CFD            Short         64386         4.9199
CFD            Short         896           4.9201
CFD            Short         4926          4.9212
CFD            Short         3422          4.9219
CFD            Short         3267          4.9325
CFD            Short         10060         4.9333

(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                         18 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