Publication date: October 10, 2025
A shadow fleet is a term used to describe vessels engaged in illegal operations aimed at circumventing sanctions, evading safety or environmental regulations, or avoiding insurance costs.[1] The term broadly refers to illegal practices occurring in the maritime sector.[2] Importantly, it is not just the cargo that is being concealed, but also the entire vessel transporting it—hence the term “shadow fleet” or “ghost fleet”. Currently, it is primarily used in the context of Russia’s efforts to circumvent sanctions. These sanctions were imposed by, among others, the EU and the United Kingdom and are a consequence of Russia’s invasion of Ukraine.
Moscow, for which oil exports are a pillar of the state budget, has begun illegally circumventing sanctions imposed by other countries, including by significantly expanding its shadow fleet. Old ships over twenty years old, with an unregulated legal status and false documentation, lack insurance, are in poor or very poor technical condition, and do not call at ports. Sailing without a flag or changing it frequently and regularly is also a common practice.[3] Furthermore, locating and identifying the owner of such a vessel is often an extremely challenging task due to complex transaction networks and the changing identity of the vessels. Ships operating in the shadow fleet manipulate the global AIS portal, which is used to track vessel movements at sea in real time. This can cause a vessel to “disappear” from radar and reappear, but under a different flag and often with a different owner. It is estimated that the shadow fleet currently consists of several hundred vessels.
To date, the European Union has adopted 18 sanctions packages in response to Russia’s military aggression against Ukraine. These include asset freezes for individuals and entities and prohibitions on providing financial or economic resources to individuals/entities on the sanctions list. In the transport sector, sanctions include closing EU ports to all Russian vessels and 444 vessels, many of which belong to the Russian shadow fleet. The EU sanctions list currently includes over 2,500 individuals and entities. Companies operating vessels belonging to the Russian shadow fleet, as well as individuals responsible for and involved in its creation, are also listed. Furthermore, G7 countries have imposed price restrictions on Russian oil sales, setting the price at $60 per barrel.[4] This has led to an escalation of Russia’s illegal oil exports.
European Commission announced the imposition of the 19th package of sanctions against Russia. It reduced the price of Russian oil from $60 to approximately $47 per barrel and increased the number of shadow tankers subject to sanctions. The new sanctions are also intended to be linked to Article 110 of the United Nations Convention on the Law of the Sea. This mechanism is intended to aid in the prosecution of unflagged vessels and thus enable the detention of shadow fleet vessels operating in, among other places, the Baltic Sea. According to the aforementioned Article, a warship encountering a foreign vessel on the high seas, other than a vessel enjoying full immunity under Articles 95 and 96, is not entitled to search it unless there is reasonable suspicion: (item d) that the vessel is without nationality.[5]
Nationality is a special legal bond that connects a ship with its state, which carries with it specific legal consequences. Primarily, a ship is subject to the laws of that state. The external manifestation of a ship’s nationality is the flag traditionally flown at its stern. Generally, a ship can only be nationalized by a single state, which exercises exclusive authority and jurisdiction on the high seas over ships flying its flag.[6]
Accordingly, if a warship encounters a foreign vessel on the high seas and has reasonable suspicion that the vessel is not national, it has the right to search it. On September 27, 2025, the French Navy detained the tanker Boracay, which belonged to the Russian shadow fleet, due to the crew’s contradictory information regarding the vessel’s origin and its failure to heed requests from French authorities.[7] This demonstrates that the sanctions mechanism based on Article 110 of the United Nations Convention on the Law of the Sea is effective and equips EU member states with tools to tighten the sanctions regime and reduce the frequency of Russia’s circumvention of it. Perhaps EU-NATO cooperation would enable even more effective actions that would facilitate the enforcement of sanctions against Russia and the elimination of the Russian shadow fleet. It is also worth noting that tankers, whether intentionally or not, leave behind huge oil slicks in the seas, which poses a threat not only to infrastructure but also poses a risk of ecological disaster to the marine and coastal environment.
Sources
[1]Sayari Masterclass webinar – Shining a Light on Shadow Fleets (accessed on October 7, 2025)
[2] https://en.wikipedia.org/wiki/Shadow_fleet – accessed on October 7, 2025.
[3]Sayari Masterclass Webinar – Shining a Light on Shadow Fleets – slide 14, accessed October 7, 2025
[4] https://www.consilium.europa.eu/pl/policies/sanctions-against-russia/ – accessed on 7 October 2025.
[5]United Nations Convention on the Law of the Sea, done at Montego Bay on 10 December 1982 (Journal of Laws of 2002, No. 59, item 543) – accessed on 7 October 2025.
[6] https://bazekon.uek.krakow.pl/gospodarka/171645912 – accessed on October 7, 2025
[7]https://businessinsider.com.pl/wiadomosci/francuzi-aresztowali-statek-floty-cieni-tak-wpadl/shb2ngn?utm_term=autor_6&utm_source=facebook&utm_medium=social&utm_campaign=businessinsider-page-post – accessed on October 7, 2025.