The threats posed by the global shadow fleet—and how to stop it

China Europe & Eurasia Maritime Security Non-Traditional Threats Russia Security & Defense Yemen

Report December 6, 2024

The threats posed by the global shadow fleet—and how to stop it

Defining the shadow fleet
Russia joins the shadow fleet
Tracking shadow vessels
Collisions, fire, disorder: The immediate harms caused by the shadow fleet
Risks posed by shadow vessels’ bunkering and refusal to use pilotage
Incidents involving shadow vessels
How flag states, port states, and coastal states contribute to the problem
Sanctions and other measures by Western governments
Environmental damage and systemic breakdown: Longer-term harm likely to be caused by the shadow fleet
Potential measures that could limit the shadow fleet’s size and activities
Conclusion

On March 2, 2024, the crude-oil carrier Andromeda Star collided with the Bulgarian-flagged cargo ship Peace in the treacherous waters between Denmark and Sweden. More precisely, the two ships collided between the Danish coastal town of Amager and the small island of Saltholm, which is located in the Øresund (the Sound) between Sweden and Denmark.¹ Because the tanker was en route to the Russian port of Primorsk to load Russian Urals crude, she wasn’t carrying the cargo of oil she would have been carrying had she been traveling in the other direction.² Had the collision occurred then, the oil would likely have leaked, causing considerable environmental harm in Danish waters. This meant that the Andromeda Star merely had to be brought to a Danish shipyard for repairs. Twenty-four days later, she was on her way again.³ At the time of writing, the Peace remains out of commission.

The Andromeda Star sails under the flag of Panama, a flag of convenience that is also the world’s second-largest flag registry (after Liberia).⁴ But she has an ambiguous identity. International maritime databases list her owner as “reported sold undisclosed interest,” meaning her owner isn’t known. Other databases list her as having been acquired in November 2023 by Seychelles-based Algae Marine Inc., a firm that, according to public records, owns no other vessels.⁵ Databases list as her manager Margao Marine Solutions OPC, a company listed at an address in the Indian state of Goa that only manages two other vessels.⁶ “Public records, however, show no such company operating at the address.

Until November 2022, the Andromeda Star was a normal oil tanker, covered by standard insurance and undergoing regular port-control inspections in Western ports. In November 2022, she passed an inspection in the Port of Houston in Texas without any problems.⁷ A year later, her ownership and management changed to Margao Marine Solutions and Algae Marine, after which she underwent no more port-control inspections until she collided with the Peace in Danish waters and had to be repaired at a local shipyard. The repairs in Denmark meant she also had to be inspected at a Danish port before being able to leave the country’s waters.⁸

The inspection completed, the Andromeda Star traveled to Primorsk, Russia’s second-largest Baltic port. Having received her cargo there, she traveled through the Baltic Sea to the Suez Canal, which she traversed on April 22.⁹ But when she reached the Red Sea, Yemen’s Houthi rebels, mistaking her for a British-owned ship, fired anti-ballistic missiles at her.¹⁰ The damage, however, was limited and the tanker could continue her journey to the Indian port of Mundra.¹¹

At the time of the collision in Danish waters, the Andromeda Star provided Danish authorities with documentation showing she was insured by Gard AS, a Norwegian firm. But when the authorities examined the documentation, it emerged that the insurance had lapsed. The Andromeda Star also provided documentation showing she was insured by the state-backed Russian underwriter Ingosstrakh. Ingosstrakh, however, reserves for itself the right not to pay out if a vessel involved in an accident has been transporting Russian oil above the price cap.¹²

The Andromeda Star turned out to belong to Russia’s shadow fleet, a collection of mostly aging ships that transport sanctioned cargo, especially crude oil. They have obscure ownership, are poorly maintained, and obfuscate the details of their identity. Many frequently obfuscate their movements by manipulating their automatic identification systems (AIS), and many also frequently change their flag registrations. This has made previously tiny ship registries including Gabon, Eswatini, the Comoro Islands, and Guinea-Bissau suddenly significant participants in global shipping: They are so permissive that virtually any vessel can register, even ones turned down by other “flag-of-convenience” states. Yet due to their insufficient maritime expertise and infrastructure, these countries will not or cannot take the action required of flag states if one of their vessels causes an accident or incident.

Summary

Since Russia’s 2022 invasion of Ukraine, the shadow fleet—which previously mostly transported goods to and from Iran and Venezuela—has exploded in size. Today, around 17 percent of all oil tankers are estimated to belong to the shadow fleet, which also comprises other merchant vessels.

When the shadow fleet was much smaller, the global maritime community could manage the risks posed by it. Today, by contrast, the fleet’s size means it poses immediate risks to a large number of crews, coastal states, vessels, and to the maritime environment.

The fleet’s size also means it poses a threat to global maritime rules. The global maritime system only functions when the vast majority of its participants voluntarily follow the rules.

Western governments’ efforts to reduce the shadow fleet through sanctions on individual vessels have only been marginally effective. There are, however, other strategies they could pursue, including engagement with the nations that flag the shadow vessels and investigations to identify and sanction shadow vessels’ ultimate beneficial owners.¹³

Defining the shadow fleet

The shadow fleet—often also referred to as the dark fleet—is not an official fleet. Instead, it is a collection of vessels that exhibit most or all the below characteristics.¹⁴ The vessels:

Have opaque ownership and management. Many companies involved are registered at post-box addresses in countries including India, the Seychelles, and the United Arab Emirates, or in extremely obscure locations in these countries. The majority of companies are only linked to one, two, or three vessels. In many cases, that may be because these are shell companies, not proper businesses. The use of shell companies means the ultimate beneficial owner (and carrier of liability) is almost impossible to identify, let alone locate. According to investigations by Pole Star, a maritime research company, in 44 percent of cases a shadow vessel, or the majority of its sister ships, “has changed its owners, operators, or managers at least three times in the past year.”¹⁵ The owners or operators of 36 percent of shadow vessels were set up after February 2022.¹⁶
Sail without the industry’s standard Western insurance (so-called P&I clubs; see fact box How P&I clubs cover contingencies).
Are old compared to other ships of the same size. Almost 70 percent of dark-fleet tankers are fifteen years or older.“¹⁷.
Tankers are typically scrapped when reaching twenty years of age, which is another reason the shadow fleet, with its large number of vessels aged over twenty, stands out. On average, very large crude carriers (VLCCs) operating as part of the shadow fleet between February 2022 and February 2023 were 18.1 years old, while officially operating VLCCs had an average age of 10.4 years.¹⁸
Often change flag registrations and almost always sail under flags of convenience. The Andromeda Star, for example, switched flag registrations in 2019 and 2023, when she was reflagged from the Marshall Islands to Panama.
Don’t undergo regular maintenance.
Often manipulate their AIS, the navigation system required on all commercial vessels for the safety of maritime traffic.

Since shadow vessels by definition operate in the shadows, it’s difficult to fully establish key aspects including how and when the fleet emerged and how fast it has grown since. What is clear, however, is that in addition to Latin American drug cartels, the Democratic People’s Republic of Korea (North Korea) is a long-standing practitioner of surreptitious shipping techniques. These techniques have been prompted by North Korea’s desire to evade United Nations Security Council sanctions imposed on it since 2006 as a result of its development of nuclear weapons. Even though these sanctions only cover the export of weapons and weapons technologies, and the import of certain food and luxury products, North Korea has systematically thwarted new sanctions with comprehensive efforts to export the sanctioned goods.

Western insurers, who dominate the market, don’t underwrite the shipment of cargo sanctioned by Western governments, and UN member states are obliged to inspect and report suspected North Korean shipments. Pyongyang, working with actors in the shipping industry willing to violate the sanctions, began to systematically disguise the identity of vessels carrying sanctioned North Korean goods. The case of the MV Light is instructive. According to a note published in 2012 by the panel of experts established pursuant to UN Resolution 1874 (2009) and monitoring the implementation of that resolution,¹⁹ the United States reported:

It had reasonable grounds to believe that the MV Light, which departed the Democratic People’s Republic of Korea in May 2011, was transporting items prohibited by resolutions 1718 (2006) and 1874 (2009). With permission from Belize, the flag State, on 26 May, a United States Navy ship hailed the MV Light and informed the shipmaster of its intention to inspect. The shipmaster responded that it was a Democratic People’s Republic of Korea ship and that it refused to be boarded and inspected. The United States therefore requested the assistance of several other Member States in the region, including inspecting the vessel should it enter one of their ports. However, on 29 May, the MV Light changed course and returned to the Democratic People’s Republic of Korea.

How P&I clubs cover contingencies

Merchant vessels are covered by hull-and-machinery insurance for the vessel itself, and by cargo insurance for the shipment. Shipowners are responsible for the hull-and-machinery insurance, while cargo owners sign insurance for their shipments. Protection and indemnity insurance (commonly referred to as P&I insurance) exists alongside cargo and hull-and-machinery insurance. It covers additional risks relating to the entire vessel, mostly ones relating to serious contingencies including oil leaks and attacks on the vessel. Because the damage from such contingencies can incur enormous costs, coverage is provided by mutual insurance associations known as P&I clubs. There are twelve P&I clubs, which in turn form an International Group of P&I Clubs. Each insured party pays into the club to which they belong. Incidents requiring payouts are paid by the club on an annual basis; if there are not enough funds available, the members make another payment into the pool.²⁰

Ever since, vessels that have been sold into the opaque market and disguise their identity while traveling have been transporting sanctioned North Korean goods to countries willing to buy these goods.²¹ The export destinations for sanctioned weapons include Russia. As a sanctioned importer of luxury goods and technology, North Korea simply pays a massive premium to the companies and individuals willing to smuggle these goods.²² The US government in particular has imposed sanctions on vessels carrying sanctioned goods to and from North Korea, but Pyongyang and its collaborators have found ways of maintaining this shadow trade.²³

Iran, too, has developed sophisticated strategies to get around sanctions imposed by the West in response to Iran’s attempts to develop nuclear weapons. The sanctions were eased as part of the Joint Comprehensive Plan of Action (JCPOA), the agreement signed by Iran, the UN Security Council’s five permanent members, Germany, and the European Union in 2015. Under President Donald Trump, however, the US withdrew from the Iran nuclear deal in 2018 and reimposed its sanctions; the agreement’s other Western partners found themselves unable to sustain the agreement’s provisions.²⁴ Since US economic sanctions include transactions in US dollars, Iran once again found itself unable to legally trade key goods, especially petroleum, on which it depends for export revenues. It increasingly did so using vessels that frequently flag-hopped and manipulated their AIS, and typically lacked P&I club insurance.

This is when monitoring of shadow vessels (or dark vessels), as they were to be unofficially labeled, began in earnest. The monitoring was conducted by companies in the shipping industry, by navies and coast guards, and by nongovernmental organizations like United Against a Nuclear Iran. For different purposes and using different formats, each entity observed vessels that appeared to be flag-hopping and turning off their AIS. Retired Vice Admiral Duncan Potts of the Royal Navy, who commanded the EU’s counterpiracy force, ATALANTA, off the Horn of Africa in the late 2010s, described his experience running counterpiracy operations:

We used to call shadow vessels “bottom feeders,” like those murky creatures. They caused us massive problems because as a force, we were flag-blind to piracy, so if anyone got into trouble, we would go and assist. That included bottom feeders, who could change flag states at the drop of a hat and had dubious insurance. I remember one such ship we had coming through. We knew it was carrying lots of arms, and it kept on breaking down and was ripe for piracy. If it had been seized by those pirates, that would have kept al-Shabaab and every jihadi in the Middle East region going for a long time. So we put ships around it to make sure that it couldn’t be seized and almost escorted it around, although we never really knew who owned it.²⁵

In September 2019, thirty-six of the seventy-five Iran-linked oil tankers tracked by United Against a Nuclear Iran were not using their AIS.²⁶ That year, the US government widened its sanctions against Venezuela, because the 2018 Venezuelan presidential election in 2018 was widely considered not to have been free and fair.. Most importantly, it sanctioned PdVSA, Venezuela’s state-owned oil and gas company.²⁷ Because Venezuela relies on energy exports for nearly two-thirds of its national budget, the country has made massive efforts to keep up exports, including through the use of shadow vessels. (The US partially eased the sanctions in 2023 but reimposed them in April 2024.²⁸)

In 2020, United Against a Nuclear Iran identified seventy shadow tankers transporting Iranian oil.²⁹ While nongovernmental organizations and companies in the shipping industry kept monitoring the growing number of shadow vessels, including ones linked to North Korea, there was no central entity collecting the information. Indeed, there seemed to be no need for one, as the unofficial fleet was still so small it didn’t seem to pose significant risks to vessels, coastal states, or marine life. Simon Lockwood, head of shipowners at WTW, the global insurance broker, put it this way:

The shadow fleet is simply a collection of vessels that operate when countries experience challenges like sanctions regimes and insurance restrictions that preclude them from operating under normal conditions. It became obvious with Iranian cargoes in the late 2010s, but it existed before that too, just in smaller volumes.³⁰

Russia joins the shadow fleet

After Russia invaded Ukraine in 2022, it was clear that the West would attempt to punish Russia— and even force it to withdraw from Ukraine—by imposing sanctions including some type of ban on Russian crude oil. P&I clubs anticipated this move and began withdrawing coverage from vessels transporting Russian crude. This meant that many vessels transporting Russian oil no longer had Western insurance, which forced them to turn to second-rate or untested insurers. This rendered many such vessels effectively uninsured. Noted Lockwood: “Insurers started to look at their own position and, in some cases, preempt what was going to happen with regard to sanctions. They ended their contracts with Russian cargo ahead of that time so that they wouldn’t be caught trying to implement cancellations after the cap had been introduced.”³¹

The calculations can be complicated when companies operating on the basis of long-standing rules and regulations try to assess how geopolitics might change those conditions. Lockwood noted:

One of the biggest challenges for insurers and brokers, and also for shipowners, is having to interpret a shifting landscape of sanctions and sanctions regimes, and then having to guess what comes next. Nobody wants to put up in a situation where they unwittingly are in breach of a sanctions regime or one that’s very close to being imposed. A challenge for lots of insurers is that they operate in a number of jurisdictions, many of which may have different sanctions regimes. And shipping exists in the world of US dollars. As a result, companies take a cautionary approach rather than risking a [sanctions] breach.³²

Underwriters’ early actions were also prompted by the complex nature of insurance, which can rarely be canceled from one day to the next and typically involves several insurers underwriting the same policy for any given vessel. “Typically for a hull-machinery policy or hull-machinery war policy, there may be ten-plus different insurers that are involved, and it could be one or several brokers. Each one of those stakeholders will have to do due diligence, run sanctions checks, and achieve approval on any action, which adds layers and layers,” Lockwood noted.³³ By November 2022, Lloyd’s List calculated that the shadow fleet had grown to some 200 vessels.³⁴

At the same time, shipowners anticipating the price cap left the Russian oil trade. This opened an opportunity for completely new actors to establish themselves, which they did. Within a very short period, a significant number of tiny outfits were formed, primarily in India, the United Arab Emirates, and Hong Kong.³⁵ The formation of such companies, which typically operate out of obscure industry-park or brass-plate addresses, continues, with most of the firms owning only a few vessels.

The Group of Seven countries, joined by the EU and Australia, imposed the cap of $60 per barrel in December 2022.³⁶ Western shipping companies and maritime insurers were allowed involvement in the shipment of crude oil below the cap, while shipment above the cap to the participating countries was banned. The insurance cancellations unsurprisingly accelerated once the oil price cap was introduced and, in tandem, so did the number of vessels sailing without P&I club insurance. The shadow fleet’s explosive growth had begun. In 2022, there were over 600 second-hand tanker sales—a record—and the tankers were often sold at unusually high prices, the US Congressional Research Service reports.³⁷ By the summer of 2023, prices for fifteen-year-old Aframax tankers—a type often used in the shadow fleet—in the second-hand market had more than doubled.³⁸ That year, only seven tankers were retired from service and sold for their scrap value, an extremely low number compared to the annual average of twenty-five to 140 tankers.³⁹

In February 2023, the commodity trader Trafigura estimated that the dark fleet had grown to some 400 crude oil vessels and 200 oil-product tankers.⁴⁰ By November 2023, the energy intelligence firm Vortexa estimated that 1,649 unique tankers had operated in the “opaque market” (i.e., fulfilling at least some of the shadow fleet criteria) since January 2021. Tankers exclusively transporting Russian oil products accounted for a staggering 66 percent of this fleet, while Iran and Venezuela together accounted for 20 percent: But 75 percent of the vessels transported oil products for Russia and also for Iran, Venezuela, or both.⁴¹ The firm’s analysts also noted that in the second quarter of 2023, Russian crude-oil and oil-product carriers “accounted for 80 percent of all opaque market tanker activity.”⁴²

In December 2023, the International Maritime Organization (IMO) attempted to at least partially stall the shadow fleet’s explosive growth. In a meeting that month, the IMO Assembly (the organization’s governing body of member states) passed a resolution that called on member states to prohibit or regulate ship-to-ship transfers. The Assembly also recommended that port states, as soon as becoming aware of vessels trying to conceal their identity or activities, “should subject such ships to enhanced inspections.”⁴³

Yet the shadow fleet continued to flourish. In May 2024, shipbroker BRS documented 787 oil tankers operating as shadow vessels—8.5 percent of the world’s total fleet. Among large ocean-going vessels (i.e., 34,000 deadweight tonnage and larger),⁴⁴ the shadow fleet representsed13 percent of the total fleet, BRS found.⁴⁵ Venezuela, where the fleet of state-owned ships has shrunk due to lack of maintenance, has even turned to dark tankers for oil exports to its maritime neighbor Cuba.⁴⁶

In September, maritime AI firm Windward estimates that a quarter of wet-cargo vessels, a total of 2,300 ships, operate outside the official shipping system.⁴⁷ A new form of shadow vessels has also appeared: so-called zombie vessels that steal the identities of legitimately operating vessels that have gone out of service.⁴⁸ Two months later, S&P Global estimated that 889 oil tankers of medium size and upwards had been used to transport sanctioned oil: 17% of the global oil tanker fleet.⁴⁹ (Since shadow vessels don’t re-enter the official sector, the departure of hundreds of vessels from the shadow fleet indicates that these aging ships have reached a point at which it’s no longer feasible to operate them.)

What are flags of extreme convenience?

Flags of convenience (FOCs)—those from shipping registries open to all vessels regardless of where their owners are based—have been a part of global shipping for decades. The practice became popular in the 1930s, when US shipping companies got around US restrictions by registering their vessels in Panama. In the late 1940s, a US businessman teamed up with the government of Liberia to establish an open registry there too.⁵⁰ Though the United Nations Convention on the Law of the Sea (UNCLOS) stipulates that there be a genuine link between a ship and the flag she flies, it doesn’t specify what constitutes such a link.⁵¹ Today Liberia, Panama, and the Marshall Islands (another open registry) dominate global flag registrations, while Greece, China, and Japan are the top three ship-owning nations.⁵² The United States is the world’s fourth-largest ship-owning nation, but ranks nineteenth in flag registrations.⁵³

As the shadow fleet has grown, nations that until recently had minimal or no maritime experience have emerged as destinations for dark vessels seeking flag registrations. The registries of Antigua and Barbuda, Cameroon, the Cook Islands, Eswatini, Gabon, Guinea-Bissau, Guyana, Honduras, Palau, San Marino, São Tomé and Príncipe, Sierra Leone, Sudan, Tanzania, and Togo have all grown unexpectedly (and in some cases have only recently been set up).

This has occurred even though such registries are not equipped to properly assist in the contingencies shadow vessels have already begun to cause.⁵⁴ Indeed, virtually all of these registries are operated by private companies, which in turn are often based in other countries, and are run as profit-making operations, not government agencies. Gabon’s and the Comoros Islands’ registries are, for example, operated out of offices in India and elsewhere.⁵⁵ (Some older, more established, flag-of-convenience ship registries are also based overseas. Liberia’s registry, for example, is based in Virginia.⁵⁶)

Such registries constitute flags of extreme convenience (the author’s term). Most of them, including Sierra Leone, Cameroon, Comoros, Palau, and Tanzania, are included in the Paris MoU on Port State Control’s gray or black lists of high-risk flag states as well as the FOC list of the International Transport Workers’ Federation (ITF).⁵⁷ Some of these growing flags of extreme convenience are so new or small that they are not even listed by the Paris MoU, an intergovernmental body monitoring maritime safety. Well-governed flag states are included in the Paris MoU’s white list.

Indeed, flag states of extreme convenience only partially adhere to the International Convention for the Safety of Life at Sea (SOLAS), or don’t adhere to it at all. SOLAS, the world’s most important treaty governing the construction, equipment, and operation of merchant vessels, states that “flag States are responsible for ensuring that ships under their flag comply with its requirements, and a number of certificates are prescribed in the Convention as proof that this has been done.”⁵⁸

Between January and July 2024, the Cook Islands added more tanker tonnage to its previously tiny registry than did Panama and Liberia. Indeed, tankers accounted for almost the entire Cook Islands registry.⁵⁹ This doesn’t mean all the tankers are shadow vessels, but it does illustrate the problem posed by flags of extreme convenience. In June 2024, Panama and Gabon accounted for 42 percent of the shadow vessel registrations.⁶⁰ At least 36 percent of vessels registered in Gabon have definitive links via group owners to Russia, and 47 percent of vessels registered there have missing or perfunctory ownership details.⁶¹ Between January and September 2024, more than one hundred tankers joined the registries of Antigua and Barbuda, Barbados, Guyana, Honduras, land-locked San Marino, and Sierra Leone after leaving traditional flag states of convenience.⁶²

The flags of extreme convenience are dominated by older vessels, another feature of the shadow fleet. Of the twenty tankers registered in São Tomé and Príncipe as of November 2024, none were built after 2006, and most were built in the 1990s.⁶³ The 186 tankers registered in Sierra Leone similarly feature a strikingly high average age.⁶⁴

The Norwegian Coastal Administration, in an internal report, noted an increase in vessels flagged in Gabon, Antigua and Barbuda, and Vietnam in Norwegian waters in 2023 and the first months of 2024. Liquefied national gas (LNG) tankers sailing through Norwegian waters were flagged in Gabon and Panama. “It is notable that we are observing an increase in ships flagged in Gabon. This increase began at the end of 2023 and looks likely to continue in 2024,” the report noted.⁶⁵ Between January and May 2024, three Gabon-flagged crude-oil tankers passed through Norwegian waters, as did three flagged in Antigua and Barbuda, three flagged in Vietnam, and one flagged in Cameroon. In 2020, 2021, 2022, and 2023, no crude-oil tankers flagged in these countries sailed through Norwegian waters.⁶⁶

In July 2024, it emerged that some flag states (thought to be flags of extreme convenience) had been approaching port state inspectors, who can detain ships that don’t fulfil safety requirements. Repeated such detentions cause flag states to be listed on the Paris MoU’s gray and black lists.⁶⁷

An internal report of the Norwegian Coastal Administration—which has been at the forefront of documenting suspected shadow vessels—notes the rapidly increasing age of crude-oil tankers sailing through Norwegian waters, a strong indication of shadow-vessel traffic. In 2020, crude-oil tankers passing through Norwegian waters had an average age of eight-and-a-half years. In 2023, their average age was twelve years; in April 2024, their average age had increased to fifteen years.⁶⁸ Between April and May, the Norwegian Coastal Administration registered eight tankers that had previously never sailed along the Norwegian coast. Of these tankers, five were twenty years or older.⁶⁹ By October, nearly two-thirds of all tankers of intermediate size or larger built before 2010 were trading sanctioned Iranian, Venezuelan, or Russian oil.⁷⁰

Different data points deliver a good picture of what Russia’s dark-fleet activity looks like. In March 2024, 223 loaded tankers lacking Western insurance left Russian ports; of these, 85 percent were fifteen years or older.⁷¹ Tankers that previously transported oil and oil products on behalf of Iran also appear to have switched to primarily servicing Russian clients. Since February 2022, “more than 92 vessels previously involved in helping Tehran export Iranian oil are now helping Moscow transport Russian oil or petroleum products,” United Against Nuclear Iran reported in May 2024.⁷² Between May and August 2024, 600 tankers carrying Russian oil traversed the Bay of Finland on their way from Russia’s Baltic ports; of these, 283 were shadow vessels.⁷³

In a September 2024 report on shadow fleet activity in the Baltic Sea, Greenpeace found that since 2021, the number of tankers departing from Russia carrying crude oil had increased by 70 percent, and during the same period the vessels’ average age had nearly doubled.⁷⁴ In 2023, nearly 1,000 Russian oil tankers sailed along the Baltic coast in a westerly direction, the highest number of Russian oil tankers ever recorded off the German coast.⁷⁵ Two-thirds of the tankers lacked P&I coverage.⁷⁶ Unsurprisingly, many of the tankers were in poor repair. The Antigua and Barbuda-flagged Chilli, for example, “has [a] history of inspection issues, with Indian authorities noting significant corrosion on its hull in July 2023,” Greenpeace notes. “In March 2024, six more defects were reported, including problems with the engine and the Inert Gas System—a safety system designed to prevent explosions caused by volatile oil vapours on tankers.”⁷⁷

But shadow tankers transporting Russian oil are only one part of the dark fleet: other shadow vessels transport chemicals or dry goods, while yet others continue to transport cargo on behalf of Iran, Venezuela, or drug cartels.

Tracking shadow vessels

Another challenge in ascertaining the size and activities of the shadow fleet is that no entity is responsible for collecting such global data. Crews on legally operating vessels (which sail alongside the shadow vessels and may collide with them because the shadow vessels disguise their movements), coast guards, marine protection organizations, nongovernmental organizations, maritime underwriters, and research organizations all collect some data, but no international body gathers all the data available. Peter Broadhurst, senior vice president of safety and security at Inmarsat Maritime, noted:

It would be possible to collect a lot more data about the shadow fleet. There are not that many ships in the world, and even if the vessels have got everything switched off, there are ways of seeing that signature. There are satellites that will take the thermal picture of a vessel and pick up the actual profile of the vessel from the reflection because the steel reflects better than the sea. The data is available.⁷⁸

Today, however, the world has no single entity in charge of gathering details about shadow vessels and collecting details gathered by others. Indeed, not even the US government has an entity in charge of gathering details about the shadow fleet. Or as The New York Times reported in February 2024:

It is unclear who the US government considers primarily responsible for identifying suspicious tankers. The Treasury is tasked with administering sanctions by investigating and blacklisting individuals or companies participating in illicit activities. But it places some of the burden on insurers to monitor for suspicious behavior through the regular release of advisories and alerts.⁷⁹

Despite the obstacles involved with identifying and monitoring shadow vessels, let alone curtailing their activities, Western governments have made increasingly energetic attempts, primarily by sanctioning individual vessels and vessel owners. They also have made more sweeping political pronouncements, such as a July 2024 “call to action” by forty-five governments, which included a plea to flag states to “adhere to the highest possible safety and pollution prevention requirements and best practices” and a plea to port states “to ensure the enforcement of the safety and liability conventions on these ships, including those that relate to ship-to-ship transfer operations and the requirement to have on board valid State certificates of insurance.”⁸⁰

In the 1990s and early 2000s, and even in the late 2010s, countries involved in violations of international rules would have been embarrassed to be called out and would have been likely to at least curtail some of their activities if called out on them. By 2024, however, the countries involved in the shadow fleet—Russia, the flag states, and the oil’s recipients—showed virtually no reaction to being called out over their shadow fleet involvement.⁸¹

Indeed, states buying sanctioned oil could rightly argue that they have no legal obligation to enforce Western sanctions such as the oil price cap. By May 2024, the top importers of Russian crude oil since the introduction of the price cap were China, India, the EU (the latter buying under the price cap), and Turkey.⁸² Neither China and India nor Turkey have expressed any regret over their imports of Russian oil.

In a further development, by the summer of 2024 Russia appeared to be expanding its shadow fleet to liquefied national gas (LNG) tankers.⁸³ This was an apparent reaction to an EU sanctions package introduced in June 2024, which among other things targets Russian LNG.⁸⁴ To date, the number of suspected shadow LNG vessel is very small, also because the global LNG-tanker fleet is much smaller than the crude-oil fleet.

Nevertheless, this development demonstrates Russia’s intention to keep operating shadow vessels despite efforts by Western governments to reduce the fleet’s size and operations through sanctions.⁸⁵ In early August, for example, the Palau-flagged LNG tanker Pioneer, which has no known insurer and was disguising its location, docked at a Russian gas facility and was later sighted off the coast of Norway.“⁸⁶ The Pioneer is managed by an obscure Indian company, Ocean Speedstar Solutions, that manages only three vessels, all Palau-flagged LNG tankers that it has been managing since May 2024.⁸⁷ Like the Pioneer, the other two vessels managed by Ocean Speedstar Solutions are suspected shadow vessels. The owner of the Pioneer is also an obscure Indian firm, Zara Shipholding Co, whose address is c/o Ocean Speedstar Solutions. Zara Shipholding owns no other vessels.⁸⁸

Collisions, fire, disorder: The immediate dangers caused by shadow vessels

On May 1, 2023, the Gabon-flagged shadow vessel Pablo exploded in busy waters off the coast of Malaysia, just outside Singapore’s crowded waters. The Aframax tanker,⁸⁹ which had switched flag registration to Gabon just six days before the incident, was traveling with a nearly empty hull after having delivered crude oil in China.⁹⁰ This prevented an environmental disaster from unfolding when the tanker caught fire. However, Malaysian authorities had to extinguish the fire, rescue the ship’s crew, and search for three missing crew members, who were eventually declared dead, and organize the salvage and cleanup, as well as the care of the surviving crew members.⁹¹

In the early hours of July 19, 2024, the Singapore-flagged product tanker Hafnia Nile and the São Tomé and Príncipe-flagged tanker Ceres I collided in nearby waters, off the coast of Malaysia. The collision caused both vessels to catch fire. As is typical for shadow vessels, the Ceres I is aging, having been built in 2001, while the Hafnia Nile is only seven years old.⁹²

Eleven days later, Malaysian authorities announced that at the time of the accident the Ceres I had been anchored due to technical problems, and despite trying to evade the tanker, “the Hafnia Nile vessel could not avoid colliding with it.”⁹³ Photos shared by the Malaysian authorities show the fire-ravaged hull of the Ceres I. The Hafnia Nile, too, was damaged by the fire and left an oil sheen at the site of the crash. Both the Pablo and the Ceres I lacked a contactable owner and manager, and neither tanker had functioning P&I insurance. (The shipping publication TradeWinds has identified the Ceres I owner as a Singapore-based brass-plate company that owns no other vessels.⁹⁴)

These collisions dramatically illustrate the immediate dangers caused by the shadow fleet, and these dangers go far beyond the harm to vessels and seafarers that experience collisions with shadow vessels. Line Falkenberg Ollestad, an adviser at the Norwegian Shipowners’ Association, highlighted one of the many details stemming from the shadow fleet causing considerable problems for other maritime participants:

If a shadow has an accident and you need a tugboat or another type of vessel to assist the shadow vessel, we’d need clearances from the government to make sure they can go in and do an operation involving a sanctions-breaking vessel. We’d need such clearances to ensure that the shipowner that does that operation does not get blacklisted or otherwise penalized. And getting a payout then from the shadow vessels’ insurance company is also very unsure.⁹⁵

Indeed, as Svein Ringbakken, managing director of the maritime war-risk insurer DNK, noted, “there are a number of avenues where a legitimate shipping company can lose out. If, for example, you’re a legally operating shipowner and your vessel is harmed in a collision with a shadow vessel, and you’ve done your due diligence and maybe have missed a point or two, or if a new company has come up and you’re caught dealing with them, you might be subject to sanctions yourself.”⁹⁶

The disorder the shadow fleet causes, and the uncertainty about who should act and pay for damages caused by shadow vessels, also illustrate the longer-term harm the fleet causes to the global maritime order.

Dangers for crews

The fact that the shadow vessels operate without serviceable insurance, are poorly maintained, and transport dangerous cargo makes working on them decidedly dangerous for seafarers. Indeed, the most immediate harm shadow vessels pose is to their crews. The Pablo’s explosion left the Malaysian authorities having to attend not just to the tanker but also to her crew, yet the Malaysians’ efforts could not undo the fact that twenty-five of the crew members had suffered physical or mental harm, or both, and three crew members had lost their lives.⁹⁷

In addition, it’s unclear how well-trained seafarers employed on shadow vessels are. Precisely because they evade regulations and don’t make stops at ports in countries that fully enforce maritime rules, shadow vessels can de facto operate as they wish. While maritime regulations require that seafarers undergo a certain amount of training, it’s not known what training and vetting seafarers working on shadow vessels undergo.

What is clear, however, is that any journey involving a shadow vessel poses more risks to seafarers than journeys on most legally operating ones (though plenty of legally operating fishing boats and other vessels are so poorly managed that they do pose considerable risks to their crews). Noted Falkenberg Ollestad:

IG insurance [the traditional insurance provided by P&I clubs] ensures that the seafarers have their salaries according to the ITF’s [International Transport Workers Federation] tariffs, and it also ensures that shipowners adhere to the MLC [Maritime Labour Convention]. One can say that P&I insurance functions as social insurance for seafarers. That means that with P&I insurance, crew members have a number of rights if something were to happen to them. The shadow fleet poses a risk for its crews, also as a result of its subpar insurance.⁹⁸

Indeed, if a shadow vessel has an accident or incident, the crew risks being abandoned by the vessel owner. Seafarer abandonment is already a serious and growing problem in the shipping industry. The crews of several dozen vessels are currently onboard abandoned vessels, which means they remain with the ship despite the owner having abandoned it. As of November 2024, many dozen vessels crewed by many hundred nationals of India, the Philippines, Syria, Bangladesh, Ukraine, Bulgaria, Croatia, Vietnam, and other countries are abandoned in ports around the world.⁹⁹ By November 2024, ninety-nine vessels have been abandoned since January 1, 2024, alone.

And, as Falkenberg Ollestad pointed out, shadow vessels’ de facto unregulated use of crews risks harming the reputation of the global shipping industry, which in recent decades has improved its treatment of seafarers. The Maritime Labour Convention, which was passed by members of the United International Labour Organization in 2006, “sets out, in a single instrument, the right of the world’s 1.5 million seafarers to decent conditions of work in almost every aspect of their working and living conditions.”¹⁰⁰ Overall, 108 nations, including Russia, China, India, Indonesia, the Philippines, and the Western world have signed and ratified the convention.¹⁰¹

In the case of the Hafnia Nile, the tanker’s insurer is likely to cover a large part of the costs associated with the evacuation and care for the crew. Crews working on shadow vessels, by contrast, operate under completely different conditions. Even though the vessels do present insurance coverage to port authorities, as insurance is mandatory, the insurance covers little. As previously mentioned, Russia’s state-backed underwriter Ingosstrakh, which insures a large number of shadow vessels, has in its insurance policies a sanctions clause that means vessels transporting oil above the price cap are not covered by the policy.¹⁰² Ingosstrakh itself was among the companies sanctioned by the UK government in June 2024, though this is unlikely to reduce the shadow fleet, as it already operates outside Western and many international rules.¹⁰³

The risk to the marine environment

The risk shadow vessels pose to the environment is immediate, as this armada comprises aging vessels that are not undergoing regular maintenance and, in addition, carry environmentally harmful cargo. The US National Oceanic and Atmospheric Administration (NOAA) lists the following environmental harm caused by oil spills:

It takes marine habitats nearly a decade or more to recover from oil spills, and the large number of animals killed in such accidents are, of course, gone forever. When the Andromeda Star collided with the Peace, only the lucky circumstance that the Andromeda Star was not carrying any oil prevented harm to Danish waters. Because shadow vessels are aging and poorly maintained, they’re also likely to experience leaks of oil and other hazardous substances in their cargo. In collision between the Hafnia Nile and the Ceres I, a serious oil spill was averted by the fact that the Ceres I was on her way to collect cargo and sailing with an empty hull.

Shadow vessels’ age and poor maintenance record thus present a significant risk to the environment. In its September 2024 report, Greenpeace notes that shadow tankers sailing from Russia’s Baltic ports along the German coast pass several bird sanctuaries and nature reserves.¹⁰⁵

Noted Broadhurst: “There are legally operating tankers that are twenty-six, twenty-seven, twenty-eight years old, with recognized companies. That’s okay if you’re maintaining them, but that’s a long time for a ship. Shady practices were already happening years ago, but the shadow fleet means they’ve become much more common. In some cases, for example, aging vessels are sold for scrap and don’t actually go for scrap but are instead used as shadow vessels. Plus, maintenance of the vessels is poor and maintenance of their safety equipment is poor.”¹⁰⁶

Under international maritime rules, ports act as ships’ primary inspectors. This system, however, depends on port authorities complying with rules. If they’re sloppy or look the other way when poorly maintained vessels enter their ports, there’s no international authority that can force them into compliance. “The shadow vessels are getting through port state controls: This is also the case because these vessels don’t travel to highly regulated ports in countries like the United States and Europe,” Broadhurst noted.¹⁰⁷ Indeed, Chinese port authorities have been found to accept fraudulent documentation from shadow vessels.¹⁰⁸

The risks posed by the shadow fleet to the marine environment and surrounding communities is compounded by shadow vessels’ habit of turning off or manipulating their AIS, which means other vessels can only know their location when it becomes visible to the naked eye, at which point efforts to avoid a collision may be inevitable. This appears to have been what happened when the Hafnia Nile collided with the Ceres I. A further risk is the weather, as poorly maintained shadow vessels struggle to cope with icy waters. “This is not a pleasant environment for our members and nor for Finland as a major catastrophe is expected sooner or later. If something happens in the winter with ice, it is impossible to clear the ice,” said Carolus Ramsay of the Finnish Shipowners’ Association.¹⁰⁹ A wintry oil spill in the Baltic Sea or other icy waters would significantly exacerbate the harm to the environment.

Costs for coastal states

The costs facing coastal states from shadow-fleet incidents are enormous. Cleaning up after just one accident involving an Aframax tanker could cost $859 million in Europe and $1.6 billion in Southeast Asia.¹¹⁰

Coastal states are naturally exposed to accidents and incidents involving merchant vessels, even when these operate legally. The International Convention on Maritime Search and Rescue (SAR), adopted in 1979 and entered into force in 1985, ensures that all parts of the high seas have access to search and rescue. Under SAR, the world’s waters are divided into thirteen search-and-rescue zones, and all coastal state signatories are obliged to participate in search and rescue within their zones.¹¹¹

Spills are, in turn, handled through a public-private partnership. Under the International Convention on Civil Liability for Oil Pollution Damage, “the owner of any oil tanker carrying more than 2,000 tonnes of oil cargo in bulk is liable for damages caused by any leaked or discharged oil, regardless of whether it was intentional or not.”¹¹² Such shipowners must obtain a so-called Blue Card from their flag states for each of their tankers in this category: The Blue Card serves as proof that a tanker has insurance covering potential oil leaks. The Blue Card allows vessels carrying oil to travel unencumbered through different coastal states’ waters, and the coastal states have reassurance that the cleanup and expense for any spills will be handled by the vessels’ insurers.

The environmental and financial harm caused to coastal states by legally operating oil tankers is also covered by the International Oil Protection Compensation Funds (IOPC), which were established in 1992 after several large oil spills had placed severe strain on the affected coastal states. The IOPC Funds are “financed by contributions paid by entities that receive certain types of oil by sea transport. These contributions are based on the amount of oil received in the relevant calendar year, and cover expected claims, together with the costs of administering the Funds.”¹¹³ This means that oil importers pay a fee into the funds, which then administer any claims by coastal states. To date, the IOPC Funds have handled compensation for 158 oil spills.¹¹⁴

In addition, maritime rules and regulations cover the salvage of vessels that are unable to move or have been damaged beyond repair in fires or other accidents. In the case of the Hafnia Nile-Celes I collision, the owners of the former appointed a nearby salvage firm, Straits Salvage Engineers, to carry out the salvage work.¹¹⁵

For the most part, shadow vessels often have P&I insurance, but according to Insurance Journal, these are often “Russian providers backstopped by a heavily sanctioned, state-backed reinsurer. In some cases, there are insurers in locations including Cameroon and Kyrgyzstan.”¹¹⁶ That makes the insurance questionable and often unusable, and because shadow vessels lack P&I club-provided insurance, they also lack Blue Cards. In addition, the recipients of their oil don’t pay into the IOPC Funds. Even if they wanted to do so, the IOPC Funds would not be able to receive the contributions, as the oil transported by shadow vessels is typically above the price cap and the IOPC Funds – being based in London – adheres to UK laws.

The growth of the shadow fleet thus means that coastal states must contend with regular traffic involving oil tankers that lack Blue Cards. DNK’s Ringbakken recounted how much things have changed since he testified before the European Parliament on behalf of the tanker industry in 2003:

There was a discussion about whether Norway should introduce exclusion zones to keep substandard ships away from our shores. And in the hearing, I told the MEPs that all the ships that were transporting oil along the Norwegian coastline were only modern tonnage with double hulls, and with experienced operating companies. If I were to testify in a similar way now today, I would not be able to say the same thing. Today coastal states are in a difficult position.¹¹⁷

P&I club insurance and Blue Cards are a maritime custom that has worked well because the vast majority of shipping companies participated in it. The fact that the now sizable shadow fleet exists outside this system places coastal states and their marine environments at considerable risk. While coastal states could, in theory, introduce requirements for all merchant vessels to possess Blue Cards and block vessels lacking such protection, countries involved in the shadow fleet would be likely to consider such a measure hostile and escalatory.

It also poses a substantial risk to the IOPC Funds. Since the funds compensate coastal states for oil spills not covered by insurance, oil spills caused by the shadow fleet would force the funds to cover the entire amount. That would quickly empty the funds’ coffers.

Risks posed by shadow vessels’ bunkering and refusal to use pilotage

The inherent threats shadow vessels pose to the environment are exacerbated by their crews’ behavior. This includes not just AIS manipulation but also refusal to use pilotage in treacherous waters and their use of bunkering, also known as ship-to-ship transfers (STS). The Danish Straits, which are narrow, busy, and difficult to navigate, are already seeing such refusals. (Shadow vessels now transport 65 percent of Russian oil shipments going through the Baltic Sea. Since early 2022, 230 shadow tankers have transported Russian crude through the Danish Straits on 741 occasions, Bloomberg reports.¹¹⁸) At the time of writing, more than one in five of the shadow vessels decline the use of pilots while passing through the Danish Straits.¹¹⁹ Though international maritime regulations don’t oblige vessels to use pilotage, it’s standard practice to do so in dangerous waters (including the Danish Straits and parts of the Suez Canal). Shadow vessels’ refusals of pilotage accentuate the norm violations institutionalized by the shadow fleet. When the shadow fleet began its rapid growth in 2022, this author considered pilotage an opportunity to rein it in: If Denmark were to refuse pilotage to suspected shadow vessels, such vessels would not travel through the Danish Straits. Instead, shadow vessels deliberately turn down pilotage to signal their ability to harm Denmark and to violate norms with impunity.

Retired Rear Admiral Nils Christian Wang, a former chief of the Danish Navy (which also has coast guard duties) said:

The risk with not using pilotage through Danish waters is that you are traveling through quite narrow straits. And if you are deep-drafted, it becomes even more narrow. Having a skilled pilot on board when you go through Danish waters significantly enhances safety. We have from time to time also had experienced ships from the Russian merchant fleet colliding with [the island of] Bornholm because the helmsman or the officer on watch was drunk and the autopilot just let the ship go right into the cliffs of Bornholm. That’s to say that shadow vessels are not the only vessels that can have accidents in the Danish Straits. But today, shadow vessels combine poor-quality shipping with not having a pilot on board, which doubles the risk of potential disaster. It’s obvious that you enhance navigational safety if you use pilotage. You could even say that good seamanship and courtesy towards a coastal nation that has hardly navigable waters requires you to use pilotage. And that’s what quality shipping companies do.¹²⁰

Should a Russian shadow vessel cause an accident in the Danish Straits by not using pilotage, there would be immediate damage to Danish waters and marine life. But because pilotage is merely good practice, not mandatory under international maritime rules, Denmark can’t ban shadow vessels that refuse pilotage. Noted Wang:

Normally a private shipping company gets proper insurance, which means it won’t go bankrupt in case of an accident. That insurance means you have to live up to the proper international insurance standards, and you also pay attention to how people view you as a shipping company when it comes to quality. That means you have a private business interest in being a good choice for transport. But the state-supported shadow fleet doesn’t operate according to normal business rules but as a state instrument and even has the purpose of not living up to international standards because that’s a way of making a statement.¹²¹

Off the eastern coast of Gotland, Russian shadow vessels have been signaling that they can harm other countries’ maritime environment in a similar manner.¹²² Several vessels have been conducting bunkering oil there, as well as in several locations in the Mediterranean including the Laconian Gulf (near Greece), Hurd’s Bank (near Malta), Ceuta (a North African enclave belonging to Spain), and the waters off the Romanian port of Constanta.¹²³ STS is a common practice among shadow vessels and involves ships transferring suspicious oil to other ships, which makes it harder to trace the oil’s origins. STS also allows importers of sanctioned oil to receive the oil without their ports having to come into contact with the shadow vessels, as the shadow vessel can transfer its oil to a legitimately operating vessel that then transports it to the recipient. But because bunkering involves the transfer of large amounts of oil between two ships, it’s also prone to leaks. On September 30, 2024, for example, two dark tankers transferring oil in the Persian Gulf spilled some 5,400 barrels of it.¹²⁴

Pole Star research shows that on any given date, more than thirty tankers carrying Russian crude travel to the Laconian Gulf to conduct bunkering.¹²⁵ The waters off the coast of Malaysia are another popular area for shadow-fleet bunkering. While STS is not illegal, any transfer of oil on the open sea poses a considerable risk of leaks.

In many cases, the vessels conduct the STS so openly as to appear deliberately provocative, but again, neither Sweden nor other coastal states can ban shadow vessels as a category, nor can they ban vessels simply because they’re linked to Russia. Off the coast of Gotland, Greenpeace has tried to shame the shadow vessels into departing by painting “Oil Fuels War” on one of them, but so far without success.¹²⁶ Nor has reporting by international media prompted vessels involved in STS to leave the waters off the coasts of Gotland, Malaysia, or in the Laconian Gulf. On the contrary, by the late summer of 2024, the activity off the coast of Gotland had increased somewhat compared to a few months earlier.¹²⁷

Vessels’ rights under UNCLOS

Article 17 of the United Nations Convention on the Law of the Sea states that “ships of all States, whether coastal or land-locked, enjoy the right of innocent passage through the territorial sea.”¹²⁸ This right to innocent passage means that countries can’t ban merchant vessels, not even vessels they suspect will engage in STS. All vessels also have the right to traverse coastal states’ exclusive economic zones (EEZs), which extend for up to 200 miles beyond the territorial waters.¹²⁹

In territorial waters, UNCLOS stipulates that “passage is innocent so long as it is not prejudicial to the peace, good order or security of the coastal State.”¹³⁰ The treaty then lists the activities considered impermissible: threats or use of force, military exercises, and other activities, espionage, criminal activities, fishing, wilful and serious pollution, research and surveying, and communications interference. In EEZs, coastal states have little such protection. Their rights are limited to sovereignty over natural resources, jurisdiction regarding the establishment of “artificial islands, installations and structures” as well as marine scientific research. Moreover, coastal states are responsible for the protection of the marine environment in their EEZs.¹³¹

Incidents involving shadow vessels

The accidents involving the Ceres I and the Andromeda Star dramatically demonstrate the dangers shadow vessels pose to coastal states, the marine environment, and legally operating vessels. The two ships are far from the only shadow vessels involved in incidents and accidents since early 2022. In total, by the summer of 2024 there had been some fifty incidents including fires, engine failures, collisions, loss of steerage, and oil spills.¹³²

In early December 2023, the Liberty, a twenty-three-year-old tanker flagged in Cameroon, went aground in the Strait of Malacca. She is thought to have been carrying some one million barrels of Venezuelan oil.¹³³ The Liberty “called at the Russian tank farm complex at Ust-Luga in June [2023], then spent August, September and October driving in geometric circles off the Angolan coast,” the Maritime Executive reported: “The location has been previously identified with the Venezuelan ‘dark fleet’ trade, in which tankers fake their location in Angola in order to hide their true operations in Latin America.”¹³⁴ She then traveled to the Indian Ocean via the Cape of Good Hope, arriving in Singapore in late November. Then, on December 2, she ran aground, forcing Singaporean authorities to dispatch five tugboats to the scene. The authorities also had to make preparations for an oil spill.¹³⁵ At the beginning of 2024, the Liberty’s name was changed to Vernal, and days later her management changed from a company in Kazakhstan to one in the Seychelles.¹³⁶ The latter, Enchanted Echo Corp, manages no other vessels.¹³⁷

Around the same time as the Liberty went aground, the Turba, a twenty-six-year-old tanker carrying Russian oil, lost steering in a busy shipping lane in the Indian Ocean. For two days, the Cameroon-flagged vessel drifted from the waters off Indonesia toward Singapore.“¹³⁸ Around a year earlier, the Young Yong, a vessel sanctioned by the United States, had run aground in the same vicinity, forcing the Indonesian Navy to conduct a difficult (but successful) refloating mission.¹³⁹

In May 2024, a Comoros Islands-flagged shadow tanker bringing crude oil from Novorossiysk to India via the Suez Canal had an engine failure in the Dardanelles, which forced the southbound lane to close for three hours.¹⁴⁰

How flag states, port states, and coastal states contribute to the problem

Without flag registries willing to allow shadow vessels to fly their flags, and states willing to let shadow vessels dock in their ports, the shadow fleet would not exist. Conversely, the shadow fleet exists because countries are willing to trade with Russia and other sanctioned nations that avail themselves of shadow vessels, and because flag-of-convenience countries are willing to let shadow vessels fly their flags. Since the beginning of 2022, China, India, Turkey, Egypt, and the United Arab Emirates have been the main recipients of Russian crude.¹⁴¹ (Price-cap coalition countries are allowed to import oil below the cap, but countries outside the coalition are under no obligations to observe it, and none of these countries have adopted the cap.) Since shadow vessels engage in ship-to-ship transfers on the high seas, not all vessels bringing sanctioned oil to the final destinations are shadow vessels, but many do. What percentage is unclear, as buyer nations’ port authorities don’t release statistics on the number of suspected shadow vessels that call at their ports. Either way, the importer countries’ port authorities let shadow vessels depart without the significant improvements needed to reach the standards set for merchant vessels.

Port states’ silence

This insufficient adherence to maritime standards makes such port states complicit in the shadow fleet’s operations, and these countries thus contribute to the harm caused by the shadow vessels. The shadow fleet will ultimately also harm the recipient nations themselves, as shadow vessels can experience accidents and incidents anywhere. As of September 2024, however, no port states that have been receiving suspected shadow vessels have announced they will cease doing so.

Flag states’ complicity

States flagging suspected shadow vessels are similarly complicit in the risks posed by the fleet. Windward lists Panama, Liberia, and the Marshall Islands as the top three, with Russia and EU member Malta rounding out the five nations flagging the most Russian shadow vessels, while S&P Global lists Panama and Gabon as the two top flag nations.¹⁴² As previously noted, the two nations flag 42 percent of Russia’s shadow fleet (according to S&P Global’s statistics), and 36 percent of Gabon-flagged vessels have definitive links to Russia.¹⁴³ Flags of extreme convenience, and in some cases traditional flag states of convenience, have taken minimal action to reduce the risks posed by Russian and other shadow vessels, as evidenced by the fact that they keep flagging suspected shadow fleets even though the risks posed by the vessels are well-documented. One partial exception is Liberia’s ship registry, which in June 2024 announced that the Russian insurer Ingosstrakh would no longer be allowed to insure vessels flagged in Liberia.¹⁴⁴ And in September, Palau suspended the flag registrations of the Pioneer, the Asya Energy, and the Everest Energy, while investigating their reported use of AIS manipulation.¹⁴⁵ Around the same time, the government of Eswatini announced it had discovered the registry run in its name, which it had reportedly been unaware of.¹⁴⁶ In September, it wrote to the IMO saying that 377 vessels flying its flag were doing so without permission.¹⁴⁷ A couple of weeks later, the Panama Maritime Authority announced that it would automatically deflag vessels involved in illegal activities.¹⁴⁸

Coastal states’ struggles

Coastal states have struggled to find measures that will protect them against the shadow fleet. In August 2024, the UAE banned Eswatini-flagged vessels from its ports; earlier in the year, it had banned vessels flagged in Cameroon.¹⁴⁹ That is, however, the extent of the UAE’s efforts to tackle the shadow fleet. Even though it’s well-known that numerous shadow fleet managers and owners have set themselves up in the UAE, the government has not cracked down on this activity.

Greece, meanwhile, has taken an innovative approach to try to deter the STS: In the late spring and early summer, it conducted a lengthy series of naval exercises in the Laconian Gulf, a popular area among ships conducting ship-to-ship transfers of Russian oil. Greek authorities issued the first traffic restriction on account of the naval exercise on April 30. The restriction, and the exercise going with it, were then gradually extended until July 15.¹⁵⁰

Sanctions and other measures by Western governments

The globalized economy has afforded Western governments enormous opportunities to punish Russia for its aggression against Ukraine. Sanctions are, of course, designed to force the offending country to end the policies for which it’s being punished. However, like Venezuela, Iran, and North Korea before it, Russia has shown no intention of doing so. Instead, its invasion of Ukraine continues. Since shipping is by nature more international than almost any other business sector, the continued war and Russia’s blatant use of shadow vessels have prompted Western governments to start sanctioning individual vessels and owners.

Sanctions

The United States has taken the lead. In October 2023, for example, it sanctioned a Liberia-flagged tanker and one flagged in the Marshall Islands.¹⁵¹ The following month, it sanctioned three shadow vessels and their owners, all UAE-based entities.¹⁵² By the end of May 2024, the US government had sanctioned forty-one shadow vessels.¹⁵³ The following month, the UK imposed its first sanctions on shadow vessels: four tankers flagged in the Cook Islands, Cameroon, and Barbados. The EU also imposed its first sanctions on vessels, a combination of twenty-seven shadow vessels and ships owned by Sovcomflot.¹⁵⁴ The Andromeda Star, discussed on the first pages of this report, was among the shadow vessels included.

By early July 2024, the United States, the United Kingdom, and the EU had together sanctioned fifty-three tankers transporting Russian oil. The sanctions were successful: That July, Bloomberg found that almost none of the ships were collecting cargo anymore.¹⁵⁵ Later that month, the UK sanctioned three more shadow tankers along with eight tankers owned by Sovcomflot, and in September it sanctioned another ten.¹⁵⁶ That meant it had sanctioned twenty-five shadow vessels, along with fifty individuals and entities.¹⁵⁷ Given the painstaking work involved in identifying the vessels and their owners, and the fact that any vessels exiting the business are easily replaced by new (though aging) arrivals in the fleet, sanctions of vessels are unlikely to make a significant dent in shadow fleet activity. The UK also sanctioned Ingosstrakh.¹⁵⁸ In response to Iran’s October 2024 missile attack on Israel, the United States sanctioned sixteen companies and twenty-three vessels, most of which are part of the shadow fleet.¹⁵⁹

Other measures

Behind closed doors, Western governments have also been pressuring flag states to refrain from flagging shadow vessels. Given that the registrations continue, this has not been a successful effort, but there are signs that such flag states may deflag shadow vessels when having them on their books turns out to be too cumbersome. On August 23, the United States sanctioned the Pioneer and her two fellow LNG tankers-cum-suspected shadow vessels managed by Ocean Speedstar Solutions. As we have seen, days later Palau temporarily suspended the vessels’ flag registrations.¹⁶⁰

Results to date

Even though sanctioned shadow vessels have mostly been rendered idle, the number of sanctioned vessels pales in comparison with the shadow fleet’s estimated total size. Indeed, the time and effort involved in establishing beyond reasonable doubt the details around every suspected shadow vessel vastly surpasses the effort involved in adding a vessel to the shadow fleet. As a result, the fleet has kept growing (although, as previously noted, its exact size is unknowable). Certain owners of tankers that are reaching retirement are decidedly open to selling their vessels to shady entities, and thus the shadow fleet, rather than paying to have them scrapped, as is standard practice when a vessel reaches retirement age.

Such is the lack of fear among shadow fleet operators that shadow vessels continue to blatantly engage in ship-to-ship transfers off the coasts of Western countries. Between April 2023 and April 2024, more than 3,100 STS operations took place off the coasts of EU member states, Norway, and the UK, according to S&P Global Commodities at Sea.¹⁶¹ Meanwhile, an estimated 124 shadow tankers in the VLCC and (smaller, midsize) Suezmax categories continue to transport Iranian oil and bunker off the coast of Malaysia.¹⁶²

Other plans and proposals by Western governments

It is obvious to Western governments that sanctions alone won’t curtail, let alone cripple, the shadow fleet. What is far less clear is what other measures they can take that would both be legal and have a decisive impact.

In June 2024, Denmark announced that it was planning “measures” together with allies.“¹⁶³ “And even though the Danish government didn’t specify the measures, immediately there was a response from Russia saying that Russia would make an appropriate response,” Wang said. “It was so obvious that this was something that was picked up immediately by Russia as a very, very serious offense to the right of innocent passage.”¹⁶⁴ Indeed, any measure by coastal states to curtail shadow vessels’ passage is likely to trigger angry responses and potentially escalation from Russia, which could accuse such nations of violating the right of innocent passage. At the end of August, Denmark said it would begin refusing entry to nearly thirty Russian vessels, including shadow vessels, though at the time of writing no ships have been refused entry.¹⁶⁵

Finland, for its part, has proposed that the EU acquire an oil-spill response vessel designated for use in the northern parts of the Baltic Sea.¹⁶⁶

Greece’s protracted naval exercise in the spring and summer of 2024 was an inspired and successful effort to keep shadow vessels engaged in bunkering out of Greek waters. However, the vessels merely moved their bunkering elsewhere. During the Greek exercise, the number of tankers conducting STS in Maltese waters quadrupled.¹⁶⁷ Moreover, it’s not possible to conduct lengthy naval exercises for the mere purpose of keeping shadow vessels away, and naval exercises would themselves present new perils. “You risk that the answer would be to have a Russian warship being in the same area to make sure the shadow vessels are not harassed. And then you suddenly have warships from each side close to each other,” Wang noted.¹⁶⁸

At the time of writing, the EU is (according to information provided to the author) considering a sanctions package that would allow its Baltic Sea member states to inspect the cargo and documentation of vessels in their waters, so as to ascertain the cargo’s origins and destinations. The planned measure is intended to deter shadow vessels from traveling through the Baltic Sea. In July 2024, the Netherlands’ Human Environment and Transport Inspectorate (ILT) inspected two suspected shadow vessels and banned them from Dutch waters.“¹⁶⁹ There’s some evidence that the Netherlands’ inspection and banning of two shadow vessels caused other shadow vessels to stay away from Dutch waters.¹⁷⁰ Such inspections, however, remain relatively rare, not least because shadow vessels rarely sail through Western nations’ territorial waters. Coastal states have far more rights to conduct inspections in their territorial waters than they do in their EEZs. (The Danish Straits are considered international passageways, not Danish territorial waters.)

In November 2024, the European Parliament passed a resolution calling for tougher actions against the shadow fleet in future EU sanctions packages. The MEPs want the EU to sanctions owners, operators, managers, accounts, banks, and insurance companies involved with the shadow fleet, and demand “the systematic sanctioning of vessels sailing through EU waters without known insurance and urges the EU to enhance its surveillance capabilities, especially drone and satellite monitoring, and to conduct targeted inspections at sea.”¹⁷¹ Such systematic sanctioning would, however, be likely to clash with the right to innocent passage.

Since shadow vessels don’t usually sail through Western countries’ territorial waters, and EEZs afford coastal states fewer rights, Western nations would have a limited basis on which to conduct inspections. They could, however, do so on the basis that the vessels pose a risk to marine life. If coastal states were to conduct large-scale inspections, however, they would face the prospect of having to detain a significant number of vessels or order them to undergo repairs. Especially because shadow vessels’ owners and insurers are so elusive, such measures would become a significant administrative and financial burden. Indeed, because shadow vessels’ owners are so obscure as to often be unreachable, and because they would at any rate be content to let go of aging shadow vessels rather than paying for repairs, coastal states face the prospect of having to indefinitely store and maintain seized shadow vessels.

A blanket ban on Russian-linked vessels from Baltic Sea countries’ waters—a proposal regularly floated in the public-policy community—may seem like an enticing idea. Banning vessels on account of their affiliation with Russia would, however, violate the right to innocent passage. Barring access to Russian-linked vessels would also expose such governments to retaliatory bans by Russia. Indeed, it would be the maritime equivalent of a no-fly zone, to which Russia could respond not just with a retaliatory ban but also with military action. Falkenberg Ollestad noted: “What we’re seeing in the Red Sea is a politicization of the shipping industry, and we’ve been seeing that for a while. If we start coming up with measures against the shadow fleet, that that can be retaliated against us in a different way.”¹⁷²

And, Wang noted, the very purpose of UNCLOS is safety, and the putting of restrictions on shipping:

And as soon as you start to put restrictions on one country, then you are basically eroding the whole construct. If Russia can’t STS twelve nautical miles off Gotland, what about a Latvian-registered merchant ship needing oil outside Australia? Every time you start to address one problem, you are creating multiple problems.¹⁷³

In addition, countries introducing such a ban would lose their standing as protectors of the rule of law. This is a not inconsiderable consideration, as their ironclad adherence to the rule of law is one of the platforms Western countries use in trying to convince other countries to do the same.

Environmental damage and systemic breakdown: Longer-term harm likely to be caused by the shadow fleet

The shadow fleet poses a challenge not just in the short term but in the longer term too. Ringbakken underscores the international nature of the shipping industry, which means that regulation, too, needs to be international:

The IMO and its predecessor the IMCO have been promoting international regulation of the shipping industry. It’s not an easy task, but they have been pretty good at it, and we have come quite far with the international regulation of shipping, with the liability conventions for oil spills, compulsory insurance for tankers carrying persistent oil. And all of this is threatened by the advent of the shadow fleet. A fleet of 10 to 20 percent of the world’s tankers operating outside this framework of regulation, compensation agreements, and setups: It definitely has the potential of undermining the system itself.¹⁷⁴

The most obvious risk is to maritime health. Oceans and marine wildlife may be able to withstand an occasional oil spill, and even then the recovery lasts years, if it’s ever complete. Even today, some animal communities affected by the Exxon Valdez oil spill in 1989 have not recovered.¹⁷⁵ Repeated spills, especially in small, shadow vessel-intense waters like the Baltic Sea, would place the ocean and marine life under enormous strain.

The shadow fleet also poses considerable risks to the global shipping system. This system is based on treaties, rules, and regulations built over several generations and especially since the end of World War II. Thanks to this patchwork of rules, global shipping has gone from being a chaotic, not to say anarchic, and extremely dangerous enterprise, to a mostly stable system that allows companies (ranging from shipowners and managers to underwriters) and governments to operate without constant fear of catastrophes or financial distress. The system works because the companies involved mostly obey rules governing matters from crews to insurance and maintenance.

With the shadow fleet, however, the global shipping system is faced with rule breaking not just by a few actors and on an occasional basis but rule breaking of a systematic kind. “We’re already seeing a fragmentation of the system and the shipping market,” Ringbakken noted. “If you’re engaged in shadow-fleet activities, I have a hard time seeing how you as a company at the same time can lift oil cargoes for the oil majors.”¹⁷⁶

That fragmentation also poses legal jeopardy for officially operating companies. “What happens if you’re in collision with a vessel that may have inadequate insurance?” Lockwood asked. “The other big thing is if the ship itself is a sanctioned entity: That could make it impossible to transfer funds in case of an incident.”¹⁷⁷ In other words, if a legally operating vessel is harmed by a shadow vessel, it may not be possible for the former to receive an insurance payout from the latter, even in the unlikely event that that vessel has functioning insurance. The fact that shadow vessels in reality lack insurance has put the shipping industry’s insurance system, painstakingly established over decades, under enormous stress. Ringbakken noted: “The liability insurers have lost more than a thousand ships—ships that were previously operating in well-regulated P&I clubs—to some fly-by-nights somewhere, if there’s insurance at all.”¹⁷⁸

The public-private system that compensates coastal states for oil spills in their waters is under similar stress. This system, managed by the IOPC Funds, was set up in 1978 to collect and administer funds for payouts to coastal states affected by oil spills. The contributions to the fund are paid by recipients of oil shipments, with the amount to be paid based on the volume received and the anticipated payouts needed in any given calendar year.¹⁷⁹ Today the IOPC operates two funds, which any country can join. However, the system only works if the number of oil spills is small, and following the Exxon Valdez and similar incidents, the oil-shipping industry’s standards have improved. As of November 2024, the IOPC Funds are administering fourteen cases, some of which date back more than two decades. In 2002, for example, the Bahamas-flagged Prestige broke in two and sank off the coasts of Spain, France, and Portugal. To date, these countries have received compensation of €147.9 million ($159.7 million) from the IOPC Funds and €22.8 million paid by the London Club, the ship’s insurer. The final compensation is estimated to reach €573 million.¹⁸⁰

The shadow fleet poses a fundamental challenge to this system. It’s unclear how the IOPC Funds, which are located in London, can enforce payments from buyers of Russian oil above the price cap, as the Funds are governed by UK legislation. At the same time, any state that is a member of the IOPC Funds—as Russia is—is entitled to compensation for spills in its waters. That means Russia can continue to operate its shadow fleet, which naturally sails extensively in Russian waters, knowing that leaks would be compensated by the IOPC Funds. Even more troublingly, the shadow fleet’s operations and its risk of regular spills could bankrupt the IOPC Funds altogether, especially since the funds can’t enforce payments from shadow vessels’ customers.

Indeed, by virtue of its size, the shadow fleet has enabled rule breaking on a systemic scale. The violators are most obviously the shadow vessels and their owners and managers, but also their flag states. In the past, flags of convenience have mostly tried to perform the duties that flag states are obliged to perform, but today there are states offering flags of extreme convenience to shadow vessels despite being unable to perform a flag state’s duties. Broadhurst noted:

The most common rule violations you’re seeing is flag states not performing the functions, all the functions that the flag state is supposed to perform: Vessels are being undermaintained, they engage in flag-hopping, and we don’t know who their true owners are. As a result, we don’t even know who is accountable when something goes wrong.¹⁸¹

This makes the shadow fleet the maritime equivalent of neighborhood gangs. As long as a neighborhood is only home to individual criminals, it can absorb these criminals’ rule breaking. When, however, neighborhood criminals organize themselves into gangs, the volume of malfeasance overpowers the rule-abiding majority. Especially since there is no global maritime policing authority, global shipping depends on participants from flag states to ship managers to obey the rules, and the shadow fleet has led to such an increase in rule breaking that it’s uncertain how the global maritime system will be able to absorb it.

Potential measures that could limit the shadow fleet’s size and activities

Systematically identifying owners, ultimate beneficial owners, and managers

As part of the effort to track vessels, Western governments should also increase their focus on identifying the individuals involved in the vessels’ management and ownership. Because the owners take pains to hide behind brass-plate companies, this would require investigative effort, but relevant expertise exists. Western governments could turn in particular to Italy’s Carabinieri and Guardia di Finanza, which have unique expertise investigating organized crime and identifying the individuals involved in it. This would serve as a deterrent to those individuals, as their involvement in the shadow fleet is based on the assumption that that they will not be identified, let alone penalized. Western governments could also make shadow fleet owners’ and managers’ names publicly available, for example on government websites, which would act as a further deterrent against involvement with the shadow fleet.

Revoking visas of those involved in shadow fleet-linked rule breaking

It’s not illegal for people and entities living outside the oil price-cap coalition countries to trade in Russian crude above the price cap. Shadow vessels’ rules violations, however, may be punishable under criminal or civil law (see above). It would also be within Western countries’ right to deny visas to persons involved in the shadow fleet and even to their family members. Western countries have long been loath to revoke the visas of hostile operators’ family members, but denying or revoking visas is within any country’s purview and can’t be considered or construed as an act of aggression.

Designating an EU agency to track the fleet

The European Defence Agency’s Maritime Surveillance project (MARSUR) or another EU agency could be selected as the agency in charge of tracking shadow vessels. It could invite tech companies to become partners in identification and tracking. The groups involved in this effort could also make wider use of existing technologies to comprehensively track shadow vessels including satellite technology. “If we’re going to tighten up and collect data,” Broadhurst said, “then it’s a move toward a digital kind of environment where there is a lot more tracking of vessels, a lot more recording of vessels; then maybe we can get on top of this situation because at the moment it’s so easy to sail under the radar and not have to comply.”¹⁸² This would also be an opportunity for tech start-ups to prove their capabilities within the area of growing emerging national-security risks.

It requires data collection, AI-assisted analysis, and exposure of offenders and facilitators, according to Broadhurst:

There’s a vessel in this position here that’s doing this or that, it’s the shadow fleet or it’s a good vessel. It’s out there. The structure around the bad boys, there is a structure for reporting that, which is what is done today when it comes to port detentions [which are the basis for the Paris MoU white, gray, and black lists]. If you’re identifying a vessel that seems suspicious, you could easily check it with the insurance companies. You could check it with a flag state, you could check it with a classification society, you could check it with the last port state control. And if you’ve got somebody who can analyze that data, effectively and by using AI, you’d have a very powerful platform that would identify offenders. If we can’t police, we can at least expose, because reputation is big in the maritime industry. We just need someone to own the process.¹⁸³

Inspecting and impounding deficient vessels

While coastal states can’t simply ban vessels linked to a particular country, they have the right to inspect vessels and impound ones that don’t meet maritime requirements. SOLAS, for example, gives government the right “to inspect ships of other Contracting States if there are clear grounds for believing that the ship and its equipment do not substantially comply with the requirements of the Convention.”¹⁸⁴ There have been regular suggestions that coastal states particularly exposed to the shadow fleet should conduct constant inspections (and resulting impoundments), thus making journeys through their waters unattractive for shadow vessels. UNCLOS, in turn, affords coastal states the right to protect themselves against “serious and wilful pollution.”¹⁸⁵ The two treaties thus give coastal states considerable rights that they could use more systematically.

This would, however, require an enormous personnel effort from the affected countries’ coast guards; indeed, they may lack the personnel needed for such an effort. In addition, as outlined above, such countries would almost certainly have to bear the costs for any impounded ships. Indeed, since shadow vessels’ owners are deliberately elusive and may be impossible to identify, coastal states impounding them would face maintaining them, providing care, repatriation, and some manner of wages to their crews, and then paying for the vessels’ scrapping.

If acting alone, coastal states would face both little success and considerable expense and risk. Wang is skeptical that a country like Denmark would act unilaterally to tackle this problem:

As a small cork in the Baltic bottle, we are always wary of taking unilateral steps toward Russia that are not backed up internationally. But we might try to get other countries onto the bandwagon in the IMO or some other organization to see if we can create an international protest against this.¹⁸⁶

Denmark and other coastal states could, for example, remind fellow IMO member states that preventing fast-growing oil spills, collisions, and other maritime accidents is in their interest. This is especially the case since they face the burden resulting from such incidents. If the IOPC Funds were to become nonoperational, they would of course face an extremely severe financial burden.

Verifying flag status

Countries trying to tackle the shadow fleet could also use flag-state verification as a reason to visit vessels. Potts noted that “flag-state verification has been used on the hash highway for drug runners as an excuse to get on board. You can request to board a vessel and say, ‘We think you’re Indian but you’re flying an Iranian flag, so we’re going to come over just to make sure because that flag is sacrosanct.”¹⁸⁷

Intervening against bunkering in the Baltic SeaThe EU could employ the Baltic Sea Action Plan, a “strategic programme of measures and actions for achieving good environmental status of the sea, ultimately leading to a Baltic Sea in a healthy state.¹⁸⁸ Russia is a signatory, as are EU nations. Since oil bunkering, with its considerable and unnecessary risks for the environment, violates the agreement, the plan’s other signatories would have the right to intervene against any STS activities.¹⁸⁹

Partnering with IndiaIndia presents another opportunity. Today, India is a protagonist in the shadow-fleet trade, both through its significant imports of Russian oil above the price cap and because a very significant number of shadow vessel owners operate from India. Indeed, Indian nationals own and operate a number of flag-of-extreme-convenience registries. Like other flag-of-convenience registries, these are privately operated, for-profit outfits.

Although no other country has the right to tell India what to do, political and maritime leaders could remind Indian leaders that it’s not in their country’s interest to so actively participate in the dismantling of the global maritime order the way it does by permitting larger numbers of shadow vessels to be owned and managed by shady outfits on its soil and by importing large amounts of oil arriving on shadow vessels. As examined in the previous report that is part of the Atlantic Council’s Maritime Threats initiative, the breakdown of the maritime order also includes the Houthi attacks on merchant shipping, which has seen countless Indian seafarers subjected to attacks. In March 2024, the Indian Navy rescued twenty seafarers from a tanker struck by the Yemeni militia¹⁹⁰Officials also could remind India that having some of the world’s worst flag registries based and operated in India, by Indian nationals, harms the country’s reputation. And they could remind Indian leaders that having shadow vessels in Indian waters presents a considerable risk to India itself.

Collaborating with nongovernmental organizations

Governments could initiate cooperation with environmental groups such as Greenpeace to bring attention to the massive risks posed by shadow vessels. Such collaboration would also bring opportunities to involve notable personalities who could bring further attention to the risk facing fish, birds, and waters. George Clooney, Leonardo DiCaprio, Bono, Lady Gaga, and Queen Mary of Denmark are among the large number of global celebrities involved in sustainability efforts. There are also celebrities in the Arabic-speaking world, India, and other non-Western countries who would be powerful voices in support of the environment and against the harm posed by the shadow fleet.

Encouraging shipowners not to sell vessels into the shadow fleet

Before entering the shadow fleet, dark vessels are owned by regular companies that operate in the official shipping sector. Though they clearly view the shadow fleet as a convenient source of income for ships they would otherwise have had to scrap (at their own expense), some would likely reconsider if helped to understand how the shadow fleet harms the official shipping sector and maritime order more widely.

Engaging with flag states of extreme convenience

International officials and maritime leaders could remind flag states of extreme convenience that making international headlines by flagging vessels so risky that no one else wants to flag them severely damages their reputation. Indeed, the reputational damage to flag states of extreme convenience far exceeds the limited revenues they receive from such flag registrations, as the registries are private companies. The Eswatini and Panama governments’ announcements of ship deflagging underlines this point.

If flag states of extreme convenience are, in fact, eager to establish themselves as flag states, Western countries could offer them assistance in developing the maritime expertise needed for them to be able to do anything other than shadow vessels. Especially since shadow vessels often flag-hop, this measure may result in some shadow vessels reflagging to another flag state of extreme convenience (indeed, more countries may allow companies to establish registries of extreme convenience). Deflagged vessels could also reflag to Russia. However, every country that stops flagging shadow vessels will help limit the shadow fleet.

Conclusion

The shadow fleet poses such a vexing challenge because it deliberately violates maritime rules and is so large that its violations pose a serious threat to the global maritime order. Each shadow vessel poses a risk to other vessels, to its crew, to the marine environment, and to coastal states; legally operating vessels’ insurers and especially coastal states face the prospect of significant expenses resulting from incidents and accidents involving shadow vessels. In the longer term, the shadow fleet poses another major risk: It threatens to undermine the global maritime order, which governments and the private sector have painstakingly built over several generations. The longer the shadow fleet continues to operate and grow, the more it establishes an alternative shipping sector that doesn’t just threaten individual vessels and coastal states but the functioning of the global maritime order.

One can argue that the West made a mistake in imposing a price cap on Russian oil, since the price cap has prompted the shadow fleet’s explosive growth, but the situation today is that the shadow fleet exists and keeps growing, and that it’s surrounded by an ecosystem of willing helpers ranging from flag states to port authorities to owners.

The shadow vessels’ participants involve not just vessels and their crews, owners, and insurers, but also nation-states. This state of affairs makes it impossible to agree on effective measures within multilateral organizations. The fact that the IMO, the global body primarily responsible for maritime matters, has been unable to stop the shadow fleet’s growth since early 2022 illustrates this dilemma. The private sector alone is not in a position to counter the shadow fleet, nor can individual coastal states throttle its activities by banning all suspected shadow vessels, as this could violate international maritime regulations and would also be denounced by Russia as illegal and escalatory. This, in turn, would further worsen the situation.

Governments committed to the global maritime order can, however, take actions that can gradually reduce the shadow fleet’s size and harm. These measures include establishing a shadow-fleet monitoring hub that can collaborate with tech start-ups to identify the best ways to identify and monitor shadow fleet participants, conducting regular inspections of suspected shadow vessels, engaging with flag states of extreme convenience to convince them not to flag shadow vessels, and engaging with India.

The Atlantic Council is grateful to the Smith Richardson Foundation for its support of this report.

About the author

Elisabeth Braw is a senior fellow at the Atlantic Council’s Transatlantic Security Initiative, focusing on geopolitics and the globalized economy as well as gray-zone and hybrid threats. She’s also a columnist with Foreign Policy and Politico Europe and the author of the award-winning Goodbye Globalization: The Return of a Divided World (Yale University Press, 2024) and the upcoming Undersea War (2026). At the Atlantic Council, Elisabeth leads the Threats to the Global Maritime Order initiative. She was previously a senior research fellow at the Royal United Services Institute (RUSI) in London. She’s the author of God’s Spies, about the Stasi’s church division (2019), and The Defender’s Dilemma: Identifying and Deterring Gray-Zone Aggression (2022). Elisabeth is a member of the UK National Preparedness Commission and a member of the Krach Institute for Tech Diplomacy’s advisory council. Before joining academia, she worked in the private sector following a career as a journalist. She is a regular op-ed contributor to the Financial Times, The Wall Street Journal, and The Times (of London).

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Image: Cargo vessels are seen near the Russky Bridge in a bay in the far eastern city of Vladivostok, Russia August 13, 2024. REUTERS/Alexander Manzyuk