Port state control and vessel inspection records

Every time a foreign vessel enters a port, the host nation's maritime authority has the right to inspect it. Those inspections — their findings, their deficiencies, their detentions — are recorded, aggregated, and made publicly available through a network of regional agreements called port state control memoranda of understanding. The Paris MoU covers European and North Atlantic waters. The Tokyo MoU covers Asia-Pacific. The United States Coast Guard runs its own parallel system. Equasis aggregates them all. The result is one of the most underused public databases in maritime OSINT: a searchable record of every vessel's compliance history, going back years, available for free, with no registration required for most portals.

For maritime investigators, PSC records serve two distinct purposes. The first is evidential: a vessel with a pattern of safety detentions, ISM Code deficiencies, or fire safety failures is a vessel whose operator has demonstrated a disregard for compliance that is relevant to any broader investigation of that operator's conduct. The second is contextual: understanding a flag state's PSC performance ranking tells you something about the regulatory environment the vessel operates in — and about the credibility of the documentation it carries.

MAR-004 covers the full workflow for PSC research: how to retrieve and read an Equasis inspection record, how to cross-reference against originating MoU portals, how to distinguish between deficiencies and detentions, what flag state performance rankings mean and how to apply them, and how to document inspection records to evidentiary standard. It is the fourth card in the Signal & Shadow Maritime Intelligence series.