Recommendation ITU-R M.585-9 (05/2022): Assignment and use of identities in the maritime mobile service

Ships participating in the maritime radio services mentioned in recommends 1 should be assigned a 9-digit unique ship station identity in the format M1I2D3X4X5X6X7X8X9 where in the first three digits represent the maritime identification digits (MID) and X is any figure from 0 to 9. The MID denotes the administration having jurisdiction over the ship station so identified.