International Mobile Satellite Organization (IMSO) (INMARSAT)

An intergovernmental organisation that oversees specified public-service obligations of recognised mobile satellite communication providers.

IMSO originated as INMARSAT but no longer operates the commercial satellite network. It oversees providers recognised for GMDSS satellite services and coordinates aspects of the Long-Range Identification and Tracking system under IMO arrangements.

Inmarsat is now a commercial service name and should not be confused with IMSO, the treaty organisation. Satellite airtime, terminals and operational services are supplied by providers, not by IMSO itself.