IMSO - International Mobile Satellite Organization


The International Maritime Satellite Organization (INMARSAT), a global intergovernmental organization, was established in 1976. Portugal acceded the Inmarsat Convention in 1979.

The main objective of this Organization was at the time to create and manage the space segments of the maritime satellite system, specially regarding the improvement of the Global Maritime Distress and Safety System (GMDSS), as well as the development of maritime public correspondence services and radiodetermination capabilities.

The INMARSAT structure consisted of the Assembly of States Parties, entrusted with the definition of the Organization's general policies and long-term objectives; the Council of Signatories, composed of representatives of signatories (operators) and responsible for the space segments management; and an executive body, headed by the Director-General.

In 1994, the first steps towards restructuring the Organization and adapting it to the new regulatory conditions and to the new competitive environment were taken, in order to enable its survival and provision of public service duties.

In this restructure context, and especially for commercial imperatives, the Organization was privatised on 15 April 1999, with the subsequent division in two different entities. Thus, Inmarsat's operational component was transferred to a public limited company - INMARSAT Ltd.  (a subsidiary of the INMARSAT Ventures plc holding company) – that assumed responsibility for the basic principles, involving, namely the compliance with public service obligations, of a global coverage, with a special focus to remote areas, as well as the management of the Global Maritime Distress and Safety System (GMDSS).

Furthermore, the intergovernmental organization remained, with a residual character and a new designation IMSO (International Mobile Satellite Organization), and its functions are limited to the supervision of the compliance with the basic principles on the part of the new enterprise.

The present structure of IMSO, which currently includes 56 States (Parties) encompasses the following bodies: the Assembly of Parties, which meets once every two years with all the parties; the Secretariat, executive body headed by the Director-General; and the Advisory Committee, that supports the Director-General, Portugal being a part thereof, since it was established.

The main instruments of IMSO are the Convention, which establishes the general principles and the respective structure (bodies and operation) and the Protocol on Privileges and Immunities, that defines the privileges and immunities enjoyed by the organization in the performance of its duties. Having regard to the fact that the amendments determining the restructure of the organization and the respective privatisation entered into force on 31 June 2001, the Operating Agreement (instrument which established the provisions for the use of the space segment and the form of funding participation of each signatory) expired on the same date.


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