At least 12 sanctioned Russian tankers used identical devices to fake their locations in the Black Sea
Tracking specialists have found that at least 12 sanctioned tankers from Russia's so-called shadow fleet operating in the Black Sea transmitted identical falsified coordinates via the Automatic Identification System (AIS), with some vessels appearing to be in two places at once. Experts describe the behaviour as a coordinated deception scheme, likely an adaptation to Ukrainian sea-drone strikes and more active EU enforcement of the oil sanctions imposed after the start of the full-scale war against Ukraine.
Key points
- At least 12 sanctioned tankers used identical devices to transmit false AIS coordinates, showing an unchanged position while actually hundreds of miles away
- Six tankers simultaneously transmitted two different AIS coordinates, appearing to be in two places at once
- On 27 August, the Russian oil tanker Pirop transmitted coordinates near the Bosphorus while also reporting a position about 800 km from the strait, near the Turkish coast
- All location messages from vessels using the spoofing devices froze at the same time: 08:13 UTC
- Vessels transmitted completely identical coordinates, even though normal AIS positions shift slightly because of motion on the water
- Most of the 12 tankers have switched to the Russian flag over the past year; only one remains under the flag of Equatorial Guinea, with fitness confirmed by the Russian Maritime Register of Shipping
- Over the summer, more than 30 shadow-fleet tankers renamed themselves using Russian words for gemstones such as Gagat, Labrador and Sapphire within days of switching flag
Why it matters
The findings suggest that what had been piecemeal AIS spoofing by individual sanctioned vessels is now a coordinated Russian operation, with identical hardware deployed across at least 12 tankers. The shift coincides with Russian vessels reflagging under Russia's own maritime rules, renaming themselves with Russian gemstone names, and adding physical defences against drones — a broader tightening of Moscow's grip on the fleet that finances its war against Ukraine. Falsified AIS data also undermines the transparency of global shipping and complicates monitoring of sanctioned oil flows.
What happened
At least 12 sanctioned tankers operating in the Black Sea were found to be transmitting falsified coordinates through the Automatic Identification System (AIS), the satellite-based tracking system used to monitor commercial shipping. Six of them simultaneously broadcast two different positions, so that on tracking maps they appeared to be in two places at once. The transmitted coordinates were completely identical across vessels using the spoofing devices, even though normal AIS positions shift slightly because of motion on the water, and the location messages from all affected vessels froze at the same moment — 08:13 UTC. On 27 August, the Russian oil tanker Pirop reported a position near the Bosphorus while simultaneously indicating that it was roughly 800 km from the strait, near the Turkish coast. Olly Ballinger, a shadow-fleet tracking specialist at University College London, said the identical behaviour points to a coordinated deception scheme. Bridget Diakun, director of research at Lloyd's List Intelligence, said the pattern is new for sanctioned shadow-fleet tankers in the Black Sea and is likely part of a Russian push to protect its maritime assets amid more active EU enforcement and more aggressive Ukrainian efforts to disrupt Russian oil exports. The manager of Pirop listed in the Equasis shipping database, She Ray Ships Co, did not immediately respond to a request for comment.
How Ukrainian sources describe it
Both supplied sources are Ukrainian media outlets, and they frame the spoofing as a Russian adaptation specifically designed to evade Ukrainian attacks in the Black Sea. Their headlines explicitly link the falsified coordinates to the war and to sanctions circumvention, presenting the activity as evidence that Russia is still finding ways to fund the war despite Western and Ukrainian pressure. The reporting foregrounds the threat to Ukraine's ability to keep disrupting Russian oil exports at sea.
Background
Russian shadow-fleet vessels have manipulated AIS data since the start of the full-scale war to obscure oil shipments and preserve revenue from sales despite Western sanctions. Over the past year, most affected tankers have switched to the Russian flag and now operate under Russian maritime rules; many have also been fitted with nets and metal structures to defend against drone attacks. The maritime intelligence firm Windward estimates the shadow fleet at 1,229 vessels over 20,000 deadweight tonnes, more than three-quarters of which are under US, UK, or EU sanctions, and reports that over 80 vessels switched to the Russian flag between July and September. Kyiv stated at the end of September that Ukrainian forces had struck more than 300 Russian vessels over the previous 11 weeks.