Holding(s) in Company

NOTIFICATION OF MAJOR HOLDINGS (to be sent to the relevant issuer and to the FCA in Microsoft Word format if possible)i

1a. Identity of the issuer or the underlying issuer of existing shares to which voting rights are attachedii:

Inmarsat PLC

1b. Please indicate if the issuer is a non-UK issuer (please mark with an "X" if appropriate)

Non-UK issuer

2. Reason for the notification (please mark the appropriate box or boxes with an "X")

An acquisition or disposal of voting rights

X

An acquisition or disposal of financial instruments

An event changing the breakdown of voting rights

Other (please specify)iii:

3. Details of person subject to the notification obligationiv

Name

JPMorgan Chase & Co.

City and country of registered office (if applicable)

Wilmington, Delaware, USA

4. Full name of shareholder(s) (if different from 3.)v

Name

J.P. Morgan Securities Plc

JPMorgan Chase Bank, N.A.

J.P. Morgan Securities LLC

City and country of registered office (if applicable)

London, United Kingdom

5. Date on which the threshold was crossed or reachedvi:

29 November 2019

6. Date on which issuer notified (DD/MM/YYYY):

03 December 2019

7. Total positions of person(s) subject to the notification obligation

% of voting rights attached to shares (total of 8. A)

% of voting rights through financial instruments(total of 8.B 1 + 8.B 2)

Total of both in % (8.A + 8.B)

Total number of voting rights of issuervii

Resulting situation on the date on which threshold was crossed or reached

14.98%

1.11%

16.09%

469,771,885

Position of previous notification (if

applicable)

15.22%

0.89%

16.11%

8. Notified details of the resulting situation on the date on which the threshold was crossed or reachedviii

A: Voting rights attached to shares

Class/type ofshares

ISIN code (if possible)

Number of voting rightsix

% of voting rights

Direct

(Art 9 of Directive 2004/109/EC) (DTR5.1)

Indirect

(Art 10 of Directive 2004/109/EC) (DTR5.2.1)

Direct

(Art 9 of Directive 2004/109/EC) (DTR5.1)

Indirect

(Art 10 of Directive 2004/109/EC) (DTR5.2.1)

GB00B09LSH68

70,376,546

14.98%

SUBTOTAL 8. A

70,376,546

14.98%

B 1: Financial Instruments according to Art. 13(1)(a) of Directive 2004/109/EC (DTR5.3.1.1 (a))

Type of financial instrument

Expirationdatex

Exercise/Conversion Periodxi

Number of voting rights that may be acquired if the instrument is

exercised/converted.

% of voting rights

Convertible Bond

09/09/2023

09/09/2023

4,653,497

0.99%

American Depository Receipt

N/A

N/A

2,500

0.00%

SUBTOTAL 8. B 1

4,655,997

0.99%

B 2: Financial Instruments with similar economic effect according to Art. 13(1)(b) of Directive 2004/109/EC (DTR5.3.1.1 (b))

Type of financial instrument

Expirationdatex

Exercise/Conversion Period xi

Physical or cash

settlementxii

Number of voting rights

% of voting rights

Cash-settled Equity Swap

05/02/2020

05/02/2020

Cash

44,745

0.01%

Cash-settled Equity Swap

28/09/2020

28/09/2020

Cash

380,680

0.08%

Cash-settled Equity Swap

19/10/2020

19/10/2020

Cash

37,989

0.01%

Cash-settled Equity Swap

10/11/2020

10/11/2020

Cash

9,852

0.00%

Cash-settled Equity Swap

02/12/2020

02/12/2020

Cash

2,686

0.00%

Cash-settled Equity Swap

14/01/2021

14/01/2021

Cash

85,296

0.02%

Cash-settled Equity Swap

04/07/2024

04/07/2024

Cash

8,477

0.00%

Cash-settled Equity Swap

07/10/2024

07/10/2024

Cash

11,303

0.00%

SUBTOTAL 8.B.2

581,028

0.12%

9. Information in relation to the person subject to the notification obligation (please mark the

applicable box with an "X")

Person subject to the notification obligation is not controlled by any natural person or legal entity and does not control any other undertaking(s) holding directly or indirectly an interest in the (underlying) issuerxiii

Full chain of controlled undertakings through which the voting rights and/or thefinancial instruments are effectively held starting with the ultimate controlling natural person or legal entityxiv (please add additional rows as necessary)

X

Namexv

% of voting rights if it equals or is higher than the notifiable threshold

% of voting rights through financial instruments if it equals or is higher than the notifiable threshold

Total of both if it equals or is higher than the notifiable threshold

JPMorgan Chase & Co.

JPMorgan Chase Bank, National Association

J.P. Morgan International Finance Limited

J.P. Morgan Capital Holdings Limited

J.P. Morgan Securities plc

14.98%

16.09%

JPMorgan Chase & Co.

JPMorgan Chase Holdings LLC

J.P. Morgan Broker-Dealer Holdings Inc.

J.P. Morgan Securities LLC

JPMorgan Chase & Co.

JPMorgan Chase Bank, National Association

10. In case of proxy voting, please identify:

Name of the proxy holder

N/A

The number and % of voting rights held

N/A

The date until which the voting rights will be held

 N/A

11. Additional informationxvi

Table 8A) Includes stock borrows of 2,500 (0.00%)

Chain of controlled undertakings:

JPMorgan Chase & Co.

JPMorgan Chase Bank, National Association (100%)

J.P. Morgan International Finance Limited (100%)

J.P. Morgan Capital Holdings Limited (100%)

J.P. Morgan Securities plc (100%)

JPMorgan Chase & Co. (100%)

JPMorgan Chase Holdings LLC (100%)

J.P. Morgan Broker-Dealer Holdings Inc. (100%)

J.P. Morgan Securities LLC (100%)

JPMorgan Chase & Co.

JPMorgan Chase Bank, National Association (100%)

Place of completion

London, United Kingdom

Date of completion

03 December 2019