The Russian shadow fleet is a clandestine network of hundreds of vessels operated by Russia to evade sanctions, following the enactment of 2022 Russian crude oil price cap sanctions by the G7 countries and European Union (EU), in response to the 2022 Russian invasion of Ukraine.
To circumvent these restrictions, vessels use complex ownership and corporate management structures, flags of convenience, and frequently change their names. Various tactics are also used to obscure the origin of their cargo, including ship-to-ship transshipment, disabling transponders, transmitting false data, and other deceptive or even illegal methods.
Background According to a November 2024 briefing by the European Parliamentary Research Service, the terms shadow fleet, dark fleet, and grey fleet do not have a consistent definition and are used interchangeably by journalists and politicians, making it difficult to assess the scale of the phenomenon. In December 2023, the International Maritime Organization (IMO) agreed on a precise definition, stating that dark fleet or shadow fleet are "ships that are engaged in illegal operations for the purposes of circumventing sanctions, evading compliance with safety or environmental regulations, avoiding insurance costs, or engaging in other illegal activities".
Shadow fleets have been used by Iran and Venezuela to avoid international economic sanctions. Russia was aware that sanctions against their country would result in a need to control oil tankers to export crude and processed oil. Tankers approaching their end of life were purchased by Russia for Russian oil companies or opportunists to rent out for a large fee to maintain the flow of oil exports. The price of such old tankers rose, with vendors making large profits from their sales. By the end of 2022 there were over 600 ships in the Russian shadow fleet, 400 of which were crude oil tankers; the fleet consisted of 1,1001,400 ships by December 2023. Of these ships, 118 have been sanctioned by the United States, the European Union (EU), or the UK. In 2025, the shadow fleet was reported as having more than tripled in size since 2022.
A major issue with the Russian shadow fleet is marine insurance: Western countries have minimum criteria for insurance, which includes verification of the condition of the ship. Two thirds of ships carrying Russian oil have insurers classed as "unknown"—with the vessels therefore lacking proper insurance. Being old, they are more prone to breakdown or leakage. in January 2024 the 18-year-old sanctioned Peria became stranded because of an anchor malfunction, which caused the closure of the Bosphorus to shipping. Shadow ship operators disguise the true owners and do not feel obliged to maintain the ships to a high standard. Turning off automatic identification systems and undertaking open sea ship-to-ship transfers of oil increase the risk of collisions and spillages.
Certain flags of convenience are favored. Gabon more than doubled its ships registry in 2023, with an estimated 98% of its tankers considered to be high risk and with no identifiable owner. The number of incidents affecting these tankers has increased to around two a month, with groundings, collisions, fire and engine failures, recovering the cost of rescuing these ships is doubtful due to the unknown owner and the unknown insurance, if any.
The Ukrainian government oversees a catalog of ships operating as part of the shadow fleet, listing 1337 ships . Various tactics are adopted to make it harder to track such vessels. These include the renaming of ships, changing their country of registration, sailing under false flags, switching off tracking signals, and broadcasting false locations. In one instance, the Arcusat, previously named the Tia, changed its IMO identification number.
Sanctioning From the autumn of 2023, companies involved in breaching the Russia Oil Price Cap Regime were investigated and sanctioned further by the U.S government. On 10 January 2025, the U.S. Dept of the Treasury added about 180 vessels, as well as traders, major oil companies, and senior Russian oil executives to the sanctioned list. In June 2025, the Australian Government placed sanctions on 60 vessels it deemed part of Russia's shadow fleet.
In July 2025, the United Kingdom sanctioned 135 oil tankers, along with the Russian companies Intershipping Services LLC and Litasco Middle East DMCC.
Finnish Customs declared the tanker Eagle S to be one of the shadow fleet, after an investigation was launched into the sabotage by Russia of the power cables linking Estonia and Finland. The vessel was seized by the Finns, and the Estonian Navy launched an operation to protect undersea cables in the Baltic Sea.
Insurance of tankers Sanctions imposed by the G7, the EU, and allied jurisdictions prohibit P&I insurers and other maritime service providers under their jurisdiction from covering shipments of Russian-origin crude oil and petroleum products sold above the agreed price cap. As a result, a large portion of Russia's shadow fleet operates outside the international insurance system. Many of these tankers rely on Russian or offshore insurers, such as Ingosstrakh. Investigations have repeatedly documented cases of vessels presenting falsified or expired insurance certificates, creating a gap in reliable coverage. The absence of dependable P&I insurance heightens risks for coastal states and the environment, as unreliable insurers may refuse to cover damages in the event of an accident. Despite efforts by international regulators and port authorities to tighten verification of insurance documentation, ships in the Russian shadow fleet can manipulate the system. The post-sanctions expansion of the fleet has increased the number of vessels lacking adequate international insurance, causing a considerable safety and environmental risk.
Any suspected breaches of sanctions by insurance companies are investigated. Sometimes when an application for insurance is made, the company receives false information about the cargo's source, price and destination, and sometimes the ship's name and IMO number.
Ro Marine, an insurance company based in Oslo, cancelled insurance on three tankers in December 2023 which were identified as non-compliant with oil price cap regulations. Fake insurance documents from Ro Marine have been used to deceive NATO countries and support Russia's shadow fleet. Following exposés by Danwatch and the Norwegian broadcaster NRK, flag states have detained ships and revoked Ro Marine's approval. NATO has since tightened controls and investigated the company.
Oil traders On 20 December 2023 the US Department of the Treasury announced sanctions against three companies that traded Russian oil at a price that did not comply with price cap rules, Voliton DMCC from the UAE, and the Hong Kong companies Bellatrix Energy Limited and Covart Energy Limited. Covart owns the oil products tanker Sanar 15 (IMO 9777670), which is also sanctioned.
Partial easing of sanctions On 12 March 2026, amid the war with Iran, U.S. Secretary of the Treasury Scott Bessent announced the temporary lifting of restrictions on the sale of Russian oil held on detained shadow fleet tankers. The decision was intended to achieve "stability in global energy markets" and remained in effect until 11 April 2026.
Legislation Despite causing tangible harm, targeted countries face significant legal hurdles in blocking the fleet. In accordance with the United Nations Convention on the Law of the Sea (UNCLOS), ships are granted the right of innocent passage through territorial waters, including the adjacent to a country's coastline. The convention also contains articles that provide for restrictions on navigation that poses a serious threat to the environment. Vessels must also obey the laws of the country it is traversing, including having proper insurance and being in good repair.
The shadow fleet uses the Danish Straits for passage. Despite the country facing an environmental threat from the barely insured vessels in poor condition that often pass the straits without local navigational assistance and proper paperwork, merchant vessels are guaranteed the right of peaceful passage through the Danish Straits under the Copenhagen Convention of 1857.
Reactions The EU published a brief titled "Russia's 'shadow fleet': Bringing the threat to light", in October 2024, outlining Russia's tactics to evade sanctions. On 14 November, the EU voted to adopt a resolution ensuring full enforcement of sanctions against Russia.
Two ships caused an oil spill with severe environmental damage in the Black Sea in December 2024 due to negligence by their Russian operators. According to Mykhailo Podolyak, an advisor to the head of the Office of the President of Ukraine, these tankers are part of Russia's shadow fleet. Following the major environmental crisis caused by the ships, the worst this century in the Black Sea region, Ukraine called for the international community to take action to deter the fleet. Latvia also called for the ships to be banned from EU territorial waters.
On 16 December 2024, twelve countries consisting of Britain, Germany, Poland, the Netherlands, the Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden) and the three Baltic states (Estonia, Latvia and Lithuania) agreed to cooperate to "disrupt and deter" Russia's shadow fleet to prevent sanctions breaches. The UK announced additional sanctions against the shadow fleet the following day.
Maritime incidents
Attacks on vessels
In late November 2025, Ukraine's Security Service (SBU) conducted drone strikes on the shadow fleet tankers Virat and Kairos off the Turkish Black Sea coast, and later claimed responsibility. This was followed by an attack on the EU-sanctioned tanker Dashan in the Black Sea. A Turkish company halted Russian-related operations after its vessel Mersin was damaged. In December 2025, the SBU executed its first long-range strike in the Mediterranean Sea, targeting a tanker that had recently delivered oil to India.
According to a report by The Atlantic citing U.S. and Ukrainian officials in December 2025, the Trump administration did not object to the Ukrainian strikes on the shadow fleet and approved assistance for them, considering them an "important tool" to put pressure on the Russian government to negotiate peace.
Enforcement actions
On 26 December 2024, the Finnish Police Rapid Response Unit Karhu, assisted by , two helicopters from the Finnish Navy and the Finnish Coast Guard, and the patrol vessel , boarded the Cook Islands-registered tanker , suspected of dragging its anchor and tearing off two submarine communication cables belonging to the Finnish company Elisa the day before.
On 21 March 2025, German authorities detained the tanker Eventin. The ship, under the flag of Panama, had left the Russian port of Ust-Luga and was heading for Egypt. The ship, which had been placed on a list of sanctioned ships by the EU in February, had lost engine power and drifted into German waters. After determining that the Eventin carried some 100,000 tons of sanctioned crude oil from Russia, German customs seized the ship and, in an unprecedented step, confiscated the cargo, theoretically transferring ownership to the German state. That decision was contested in a Munich court, which ruled in December 2025 that ships in distress that entered German waters, were not to be seized. The court suspended the measure, but did not decide the fate of the oil.
On 11 April 2025, the Estonian Navy minehunter seized the flagless tanker Kiwala in the Baltic Sea. The ship, which claimed it was registered in Djibouti, had been sanctioned by the EU and the UK, and was on its way to load oil in Ust-Luga. It was released on 28 April.