Dark Fleet
Ageing, opaquely owned and often uninsured tankers that move sanctioned oil while disguising their movements.
The "dark fleet" (or "shadow fleet") describes vessels — typically older tankers with murky ownership and substandard or absent mainstream insurance — used to carry sanctioned crude and products outside normal compliance channels. They rely on tactics like AIS gaps, identity manipulation and ship-to-ship transfers to obscure cargo origin.
Dark-fleet activity raises safety, environmental and compliance risk far above the market norm. We flag it from evidence-backed detectors — sanctioned ownership combined with prolonged AIS absence, age and STS behaviour — rather than from a single signal, with the method documented openly.
On TheMaritime
Also known as: dark fleet, shadow fleet, ghost fleet.
Related terms
Automatic Identification SystemAIS
A VHF transponder system that broadcasts a ship’s identity, position, course and speed for collision avoidance and tracking.
Ship-to-Ship TransferSTS
Transferring cargo directly between two vessels moored alongside, often at anchor or offshore rather than at a terminal.
Sanctions
Government measures restricting trade or dealings with designated entities, vessels, cargoes or jurisdictions.
AIS Spoofing
Falsifying a ship’s broadcast position or identity on AIS to disguise where she really is or what she really is.
Plain-English reference definition — our own explanation of a standard shipping concept, not a licensed source or legal advice. See the full glossary or the broader maritime dictionary.
Last reviewed: June 2026.