AIS spoofing presents false identity, conceals voyage details or masks movement.
UK Office of Financial Sanctions Implementation guidance defines these outcomes specifically. The manipulation allows a ship to broadcast different identifying information and can conceal its next port of call or other voyage information. The same guidance describes manipulation used to mask movement. These are the primary high-level objectives documented in regulatory contexts.
US Coast Guard guidance describes AIS as an open, unencrypted system in which false or ghost targets are technically possible. It advises corroboration and reporting rather than reliance on the AIS display alone. Legitimate AIS disablement for safety, poor transmission, sensor or configuration faults, stale manual input and deliberate manipulation are different explanations for missing or incorrect AIS information.
AIS is supplementary information and discrepancies should be assessed against radar, visual observations and other available safety information rather than treated as proof of spoofing, purpose or actor.
