Dark Shipping, Sanctions Evasion, and Maritime Gray Infrastructure
The sanctions did not isolate the adversary. They built the adversary a navy.
On December 15, 2024, two Russian oil tankers, the Volgoneft-212 and the Volgoneft-239, both over fifty years old and originally designed for river navigation, broke apart in a storm in the Kerch Strait and spilled approximately 4,000 tonnes of heavy fuel oil into the Black Sea. Russia’s own Water Problems Institute called it the worst ecological disaster of the 21st century. The mazut spread across hundreds of kilometers of coastline from Crimea to the Sea of Azov, killing thousands of seabirds and over a hundred cetaceans. Six months later, oil was still leaking from the sunken hulls. Both tankers were shuttling fuel to the FIRN, a shadow fleet storage vessel operating in the Kavkaz transshipment area. This was not a hypothetical risk. This was the predicted consequence of a system that Western sanctions created and no Western institution controls.
The Fallacy: Sanctions as Containment
Western sanctions against Russia, Iran, and North Korea are framed as economic containment. They assume that cutting a state off from the global financial and trade system isolates it. The assumption is wrong. The sanctions did not isolate these states. They displaced their trade into a permanent parallel maritime infrastructure: a fleet of aging tankers, bulk carriers, and cargo vessels operating with falsified identification, spoofed transponders, and complicit port states. Any adversary can plug into this infrastructure. Any sanctioned cargo can move through it.
The fallacy is that sanctions contain. They do not. They displace. And displacement creates infrastructure that persists after the sanctions end.
The Center of Gravity: The Dark Fleet
The fleet’s scale defies the containment narrative. As of September 2025, S&P Global Commodities at Sea dataidentified 978 tankers in the shadow fleet, representing a combined capacity of 127 million deadweight tonnes, approximately 18.5 percent of the entire global oil tanker fleet. Broader estimates from Lloyd’s List Intelligence and shipbroker Gibson placed the total between 1,200 and 1,600 tankers, roughly one-fifth of the world’s tanker capacity. A CSIS analysis from October 2025 estimated Russia’s portion alone at 435 to 591 vessels, transporting 3.7 million barrels per day, generating $87 to $100 billion in annual revenue: a figure that matches or exceeds the total value of economic and military assistance provided to Ukraine since the war began.
This is not a Russian phenomenon. It is a convergent system. Iran’s shadow fleet comprises 170 tankers with 34.2 million deadweight tonnes, including 86 Very Large Crude Carriers active in the Persian Gulf and Southeast Asian waters. Venezuela’s crude exports, largely carried by shadow vessels, averaged 711,000 barrels per day in 2025. S&P Global documented 193 tankers shared across multiple sanctioned states, carrying Iranian oil one voyage and Russian crude the next. The networks overlap. The methods are interchangeable. The infrastructure is shared. Chinese ship-to-ship transfers off Malaysia’s east coast funnel Iranian and Venezuelan crude into Chinese refineries through intermediary tankers that disable their transponders in the transfer zone and reappear on tracking systems only after the cargo has been laundered.
The ecological risk is no longer theoretical. CSIS estimated cleanup costs from a shadow fleet disaster at $859 million to $1.6 billion, costs passed to European taxpayers or coastal states because 60 percent of the fleet lacks insurance and 72 percent of vessels are over 15 years old. The Kerch Strait disaster proved the estimate conservative. The Prestige disaster of 2002 spilled 63,000 tonnes of fuel oil off Spain from a 26-year-old single-hull tanker that was carrying 77,000 tonnes. The shadow fleet carries orders of magnitude more aggregate risk: hundreds of vessels in worse condition, with no identifiable insurer, no accountable owner, and no flag state willing to accept responsibility.
The Convergence Gap
Maritime security analysts see each actor’s sanctions evasion separately. Sanctions compliance officers see financial mechanisms. Insurance industry analysts see the growth of non-Western reinsurance markets. Environmental regulators see the ecological risk of uninsured vessels. Intelligence agencies track individual ship movements. The irregular warfare community sees maritime gray zone operations.
Nobody has converged Russian dark shipping, Iranian sanctions evasion, Chinese ship-to-ship transfers, North Korean maritime smuggling, flag-of-convenience exploitation, AIS spoofing infrastructure, environmental risk, and the emerging use of shadow fleet vessels as platforms for submarine cable sabotage into a unified concept: a permanent gray zone maritime infrastructure that any adversary can access, that survives any individual sanctions regime, and that constitutes a standing challenge to the rules-based international order. This is the gap. Not intelligence. Synthesis.
Naming the Weapon: The Phantom Fleet
I propose the term The Phantom Fleet to describe the permanent parallel maritime infrastructure created by the convergence of multiple states’ sanctions evasion operations into a shared, interoperable, and self-sustaining dark shipping network. The Phantom Fleet is maritime gray infrastructure: a system that operates below the threshold of armed conflict, outside the enforcement capacity of any single regulator, and across jurisdictional boundaries that no existing authority can bridge.
The Fleet operates through three layers. The vessel layer: aging ships with obscured ownership, disabled transponders, and flag-of-convenience registration, cycled through name changes and flag hops that frustrate tracking and accountability. Gabon has more than doubled its ship registry since 2023, with an estimated 98 percent of its tankers classified as high risk. Panama, which accounts for 22 percent of shadow fleet registrations, deregistered 128 Russian-linked vessels after Western sanctions, but the vessels simply reflagged elsewhere. The financial layer: non-Western insurance markets, complicit port states, and shell company networks processing transactions beyond Western enforcement reach. Two-thirds of vessels carrying Russian oil operate with insurers classified as unknown. The operational layer: ship-to-ship transfers, AIS spoofing, and route manipulation that defeat surveillance, combined with the emerging use of these vessels as platforms for infrastructure sabotage, as the Eagle S cable-cutting incident in Finnish waters demonstrated.
The Eagle S Precedent: From Sanctions Evasion to Infrastructure Warfare
On December 25, 2024, the Cook Islands-registered tanker Eagle S severed two submarine communication cables belonging to the Finnish company Elisa while transiting the Gulf of Finland. The Finnish Police Rapid Response Unit, backed by naval and coast guard assets, boarded the vessel the following day. Estonia’s attempted interdiction of the crude oil tanker Jaguar prompted the scrambling of Russian fighter jets, confirming that Moscow treats the shadow fleet as a strategic asset worth protecting with military force.
The significance is structural. A fleet assembled to evade oil sanctions has become a platform for hybrid operations against NATO infrastructure. Vessels with obscured ownership, disabled tracking, and no accountable flag state can drag anchors across submarine cables, conduct surveillance of critical infrastructure, and serve as platforms for intelligence collection, all with plausible deniability built into their operating model. The Phantom Fleet is no longer merely an economic evasion mechanism. It is a dual-use military asset.
The Western Response, and Its Structural Failure
The enforcement response has been significant in scale and inadequate in architecture. Between January and May 2025, the United States, EU, and UK imposed coordinated sanctions on approximately 270 tankers, three times the number blacklisted in January. Germany seized the tanker Eventin in March 2025 after it drifted into German waters carrying 100,000 tonnes of sanctioned Russian crude, an unprecedented confiscation later contested in a Munich court. Estonia’s navy seized the flagless tanker Kiwala in the Baltic in April 2025. Twelve European nations agreed in December 2024 to cooperate to disrupt and deter the shadow fleet. Germany now requires tankers transiting the Baltic to submit proof of oil pollution insurance.
And the fleet grows anyway. Every sanctioned vessel is replaced. Every deregistered flag is swapped. Every compliance mechanism spawns a new evasion technique. The structural problem is that sanctions are designed to work within a system of rules that the shadow fleet exists to circumvent. Sanctioning individual ships is playing whack-a-mole against a system that regenerates faster than enforcement can strike. The fleet grew from a few hundred vessels before the Ukraine invasion to nearly a thousand by 2025, absorbing every sanction wave like a distributed network absorbs individual node failures. This is not enforcement failure. It is architectural mismatch: a rules-based system attempting to contain an adversary that has built an entire infrastructure outside the rules.
Five Pillars: Toward Maritime Transparency
Pillar One: The Dark Fleet Index. A real-time, publicly available metric quantifying the size, composition, and activity of shadow fleet operations globally. Vessel age, insurance status, AIS compliance, ownership transparency, and port state inspection rates, briefed as a maritime security indicator with the same urgency as nuclear proliferation tracking. The data exists: S&P Global, Lloyd’s List, Windward, and national intelligence services all maintain partial pictures. Converge them into a single dashboard and make it public. Transparency is the cheapest weapon against opacity.
Pillar Two: AIS as Critical Infrastructure. Mandatory AIS transmission for all commercial vessels in international waters, enforced through port state denial of entry for non-compliant vessels. AIS spoofing treated as a maritime offense equivalent to flying a false flag. The technology to detect AIS manipulation exists, deployed by firms like Windward and Spire Global, but enforcement remains voluntary. Make it mandatory. Detection without consequence is surveillance theater.
Pillar Three: Insurance as Enforcement. Coordinated policy requiring that any vessel transiting allied waters or using allied port services carry insurance from a regulated market with sanctions compliance obligations. Germany’s July 2025 requirement for Baltic tankers to prove oil pollution insurance is the template. Extend it to every European strait, canal, and exclusive economic zone. The gap between Western insurance withdrawal and non-Western insurance emergence must be closed through market coordination, not left as an enforcement vacuum that the adversary fills.
Pillar Four: Flag State Accountability. Consequences for flag-of-convenience states that register vessels engaged in sanctions evasion, AIS spoofing, or environmental violations. Panama deregistered 128 vessels after sanctions pressure. Gabon doubled its registry by absorbing the vessels Panama rejected. Without consequences for enabling states, deregistration is displacement, not enforcement. Flag states that profit from opacity must bear the cost when that opacity produces oil spills, cable sabotage, or maritime casualties.
Pillar Five: Environmental Liability Before the Next Disaster. An international instrument establishing strict liability for oil spills from uninsured vessels, with enforcement against beneficial owners, operators, and complicit port states. The Kerch Strait disaster demonstrated what happens when uninsured, uninspected vessels carrying hazardous cargo operate in ecologically sensitive waters with no accountable party. The Prestige spill led to €1.5 billion in court-ordered compensation. The shadow fleet operates thousands of vessels in comparable or worse condition. The framework must exist before the next detonation, not after.
Not My Responsibility! Everyone Cries
A tanker loaded with Russian crude oil turns off its transponder in the Baltic. It transfers its cargo to a second tanker registered to a shell company in Dubai. That tanker carries insurance issued through an entity in Mumbai with no history in the maritime sector. It delivers the oil to a refinery in China, where it enters the global supply chain as a product of unknown origin.
The ship is old. It has not been inspected. It carries no Western insurance. If it breaks apart, no one pays for the cleanup. If it collides with a submarine cable, no flag state accepts responsibility. If it is tracked, it disappears from AIS and reappears under a different name, a different flag, a different shell company, sailing the same route with the same cargo for the same purpose.
This is not a single ship. It is a fleet of nearly a thousand vessels generating $100 billion a year. It is permanent. It is available to any state willing to operate outside the rules. And it was built not despite Western sanctions but because of them.
This article names the fleet. The Kerch Strait buried the pretense that it was merely a compliance problem. It is a standing gray zone navy, and it is time the West treated it as one.
RESONANCE
Babanina I (2025). The Ongoing Environmental Impact of the Kerch Strait Oil Spill. Conflict and Environment Observatory. https://ceobs.org/the-ongoing-environmental-impact-of-the-kerch-strait-oil-spill/. Summary: Six-month assessment documenting ~4,000 tonnes of mazut spilled from two 50+-year-old tankers, with oil still leaking from sunken hulls and secondary pollution expected through summer 2025.
CSIS. (2025). Ghost Busters: Options for Breaking Russia’s Shadow Fleet. Center for Strategic and International Studies. https://www.csis.org/analysis/ghost-busters-options-breaking-russias-shadow-fleet. Summary:Estimates Russia’s shadow fleet at 435-591 vessels generating $87-100 billion annually, with 72% of ships over 15 years old and cleanup costs of $859 million to $1.6 billion per major incident.
Dryad Global. (2025). Russia’s Shadow Fleet Has Tripled Since 2022. Via Ukrainska Pravda. https://www.pravda.com.ua/eng/news/2025/07/03/7520061/. Summary: Documents fleet growth from under 100 vessels to 300-600 by early 2025, with 40% acquired from EU sellers, typical vessel age of 20-25 years, and coordinated Western sanctions covering approximately 270 tankers.
European Policy Centre. (2025). Europe’s Security Begins at Sea: It’s Time to Counter Russia’s Shadow Fleet. European Policy Centre. https://www.epc.eu/publication/europes-security-begins-at-sea-its-time-to-counter-russias-shadow-fleet/. Summary: Analysis of the shadow fleet as a full-spectrum security threat, documenting the Eagle S cable sabotage, the Jaguar interdiction prompting Russian fighter jet scramble, and UNCLOS enforcement authorities available to coastal states.
Greenpeace Ukraine. (2024). The Oil Spill Accident in the Black Sea Demonstrates What Environmental Damage Old Tankers with Russian Oil Can Cause. Greenpeace Ukraine. https://www.greenpeace.org/ukraine/en/news/3230/about-the-environmental-disaster-in-crimea/. Summary:Identified 192 high-risk shadow fleet tankers threatening Baltic and Black Sea ecosystems, with both Kerch Strait vessels linked to the shadow fleet’s oil transshipment operations.
Insurance Journal. (2025). Shadow Tanker Fleet Grows More Slowly as Western Sanctions Target Russian Oil. Insurance Journal. https://www.insurancejournal.com/news/international/2025/08/13/835611.htm. Summary:Reports shadow fleet at 1,200-1,600 tankers per Lloyd’s List Intelligence and Gibson, approximately one-fifth of the global tanker fleet, with growth slowing as sanctions increase.
ITOPF. (2021). Case Study: Prestige, Spain/France, 2002. International Tanker Owners Pollution Federation.https://www.itopf.org/in-action/case-studies/prestige-spain-france-2002/. Summary: Technical documentation of the Prestige disaster: 77,000-tonne cargo, estimated 63,000 tonnes spilled, 1,900 km of affected shoreline, combined at-sea recovery of approximately 50,000 tonnes of oil-water mixture.
Kyiv Independent. (2025). Russia’s Oil Tanker Crash Causes Worst Ecological Catastrophe, with Black Sea in Need of a Decade to Recover. Kyiv Independent. https://kyivindependent.com/russias-oil-tanker-crash-causes-ecological-catastrophe-with-black-sea-in-need-of-a-decade-to-recover/. Summary: Investigative reporting on the Kerch Strait disaster, documenting Russia’s failure to respond within critical first days and shadow fleet’s role in funding approximately one-third of Russia’s military budget.
S&P Global Commodities at Sea. (2025). Shadow Fleet Expands to Maintain Sanctioned Oil Flows. S&P Global. https://www.spglobal.com/energy/en/news-research/latest-news/crude-oil/090325-factbox-shadow-fleet-expands-to-maintain-sanctioned-oil-flows. Summary: Data showing 978 shadow fleet tankers with 127 million dwt capacity (18.5% of global fleet), with Russia controlling 561 ships and 193 tankers shared across multiple sanctioned states.
S&P Global Market Intelligence. (2025). Maritime Shadow Fleet: Formation, Operation and Continuing Risk for Sanctions Compliance Teams. S&P Global. https://www.spglobal.com/market-intelligence/en/news-insights/research/maritime-shadow-fleet-formation-operation-and-continuing-risk-for-sanctions-compliance-teams-2025. Summary: Identifies 940 unique shadow fleet vessels (45% increase), with 3,154 individual ships involved in Russian oil transport since December 2022, constituting 48% of the global tanker fleet.
Ukraine War Environmental Consequences Work Group. (2025). Military Oil Spill: How the Kerch Strait Tanker Disaster Is Linked to Russia’s Shadow Fleet Oil Exports. UWEC Work Group. https://uwecworkgroup.info/military-oil-spill-how-the-kerch-strait-tanker-disaster-is-linked-to-russias-shadow-fleet-oil-exports/. Summary: Detailed investigation linking both Kerch Strait tankers to the FIRN storage vessel and shadow fleet transshipment operations, with Ukraine’s sanctions website listing 570 shadow fleet vessels.
Windward/Vortexa. (2025). Illuminating Russia’s Shadow Fleet. Windward AI. https://windward.ai/knowledge-base/illuminating-russias-shadow-fleet/. Summary: Joint analysis documenting gray fleet carrying 1.4 million barrels per day (111% increase post-invasion), with over 1,000 gray vessels identified globally and the cleared fleet shrinking from 82% to 75% of all tankers.