Shadow Fleet
Ageing uninsured tankers moving sanctioned oil via AIS spoofing and ship-to-ship transfers.
Last refreshed: 1 April 2026
How do 940 uninsured tankers move four million barrels a day undetected?
- What is the shadow fleet?
- A network of roughly 940 ageing tankers that use AIS manipulation, ship-to-ship transfers, flag hopping, and shell company ownership to transport sanctioned oil from Russia, Iran, and Venezuela outside Western enforcement.
- How big is the shadow fleet?
- By mid-2025 the fleet numbered approximately 940 vessels, representing 17 to 19% of the global tanker fleet and moving an estimated 4 million barrels per day.
- Why is the shadow fleet dangerous?
- Vessels average 20 years old and lack P&I Club insurance. The December 2024 Kerch Strait spill, when two shadow fleet tankers broke apart, demonstrated the environmental risk of uninsured end-of-life vessels.
- Who created the shadow fleet?
- Iran pioneered the tactics from 2010 as sanctions cut its oil exports. Russia expanded the fleet by 70% in nine months after the 2022 Ukraine invasion. Venezuela adopted the Iranian model from 2019.
- What are Western countries doing about the shadow fleet?
- The Royal Navy closed the English Channel to shadow fleet traffic, Sweden and Belgium detained tankers under false flags, and the EU shifted to sanctioning fleet operators. By early 2026 roughly 270 vessels were on combined sanctions lists.Source:
- Does the shadow fleet have insurance?
- The International Group of P&I Clubs, which covers 90% of the world's oceangoing fleet, has largely withdrawn from sanctioned trades. Russian and secondary insurers cannot cover major pollution events.
- How does the shadow fleet evade detection?
- Core methods include disabling AIS transponders, conducting ship-to-ship transfers at sea to sever the paper trail, re-registering under flags of convenience, and obscuring beneficial ownership through shell companies.
Background
The shadow fleet now dominates sanctioned oil transit through the Strait of Hormuz, with roughly 940 vessels representing 17 to 19% of the global tanker fleet and moving an estimated four million barrels per day of Russian, Iranian, and Venezuelan crude. The fleet carries the majority of Russian crude exports, sustaining revenues above the G7 price cap.
Iran pioneered shadow fleet tactics from 2010 as sanctions cut exports from 2.5 million to one million barrels per day. Russia expanded the fleet by roughly 70% in the nine months after its February 2022 invasion of Ukraine. Vessels average 20 years old, with 60% aged 20 or over. The International Group of P&I Clubs, covering 90% of the world's oceangoing fleet, has largely withdrawn, leaving vessels without meaningful pollution or salvage coverage.
Western countermeasures have intensified. The Royal Navy closed the English Channel to shadow fleet traffic. Sweden, Belgium, and France detained tankers operating under false flags, while the EU shifted to targeting fleet operators directly. By early 2026 the combined US, UK, and EU sanctions list covered approximately 270 vessels.
