Yes. The MMSI for US vessels operating in US waters is the only identity code that should be used by all of its communication devices that require the a code. MMSI numbers are not transferrable and may only be used by the current registered owner of record for the vessel. If the registered owner moves, he or she can request an update to the registered address and contact information. In most cases, if a vessel is sold or transferred, the MMSI must be decommissioned and the new owner must reapply for a new MMSI. For additional guidance concerning MMSI registration, please contact BoatUS or the US Coast Guard