(ICAO) and the IMSO was signed in Montreal, Canada, on 20 September 2000 and addresses the relationship between ICAO and IMSO. As of November 2018, Inmarsat has 103 state parties that represent approximately 95 per cent of the gross tonnage of the world's merchant fleet. References External links Official website of IMSO Aviation safety Communications satellite operators Emergency communication Emergency management Intergovernmental organizations established by treaty International organisations based in London Maritime safety Organisations based in the London Borough of Islington Organizations established in 1979 Satellite telephony 1979 establishments in England zh:国际移动卫星组织