Inmarsat Regulatory News (ISAT)

Inmarsat plc ("Inmarsat" or the "Company")

Publication of the 2018 Annual Report and 2019 Annual General Meeting Notice

Inmarsat will today publish and post to shareholders its Annual Report for the year ended 31 December 2018 (the 'Annual Report'), together with its 2019 Annual General Meeting Notice (the 'Notice').

The Annual Report and the AGM Notice is available at investors.inmarsat.com.

In accordance with Listing Rule 9.6.1, an electronic copy of the Annual Report, the AGM Notice and form of proxy will be submitted to the National Storage Mechanism and should be available shortly for inspection at www.morningstar.co.uk/uk/NSM.

The information set out in the Appendix, which is extracted from the Annual Report, should be read in conjunction with the Final Results Announcement released on 7 March 2019, which includes a condensed set of consolidated financial statements for the year ended 31 December 2018, an indication of the important events that have occurred in the reporting period and a description of Inmarsat's principal risks and uncertainties. That information, together with the information set out in the Appendix, constitutes the material required by Disclosure Guidance and Transparency Rule 6.3.5 which is required to be communicated to the media in full unedited text through a Regulatory Information Service. This announcement is not a substitute for reading the full Annual Report. Page and note references in the Appendix are page and note numbers in the Annual Report and Notes to the Financial Statements.

Alison Horrocks

Company Secretary

+44 20 7728 1626

Appendix

DIRECTORS' RESPONSIBILITY STATEMENT

Each of the Directors whose names can be found on pages 62 to 64, confirm to the best of their knowledge:

v the financial statements, prepared in accordance with the relevant financial reporting framework, give a true and fair view of the assets, liabilities, financial position and profit or loss of the Company

and the undertakings included in the consolidation taken as a whole

v the Strategic Report includes a fair review of the development and performance of the business and the position of the Company and the undertakings included in the consolidation taken as a whole, together with a description of the principal risks and uncertainties that they face and

v the Annual Report and financial statements, taken as a whole, are fair, balanced and understandable and provide the information necessary for shareholders to assess the Company's performance, business model and strategy.

RELATED PARTY TRANSACTIONS

In the normal course of operations the Group engages in transactions with its equity-owned investees Navarino UK and JSAT Mobile Communications Inc. These transactions represent sales of airtime and equipment and are measured at the amounts exchanged. Group revenue from the related parties for the 2018 financial year was $39.7m and $15.6m, respectively (2017: $38.1m and $16.9m, respectively). The amount receivable from the related parties at 31 December 2018 was $17.2m and $1.7m, respectively (2017: $12.6m and $1.7m, respectively).

Amounts owing to the Executive as at 31 December 2018 is $1.4m (2017: $1.2m) and relates to remuneration earned in the normal course of operations (see note 8).