The Quiet Siege of the Baltic: How 'Shadow Fleets' Are Rewriting the Rules of Maritime Trade

A rusting tanker with no traceable owner, no real insurance and its transponder switched off is no longer a scandal. It's a business model — and it's raising costs for everyone.

By the Jester Desk · September 17, 2026

In December 2022, the G7 and the European Union capped the price of Russian seaborne crude at $60 a barrel. By 2025, the shadow fleet moved roughly 3.7 billion barrels of oil — nearly 7 percent of global crude flows, according to the American Action Forum.^[11][12][14]

The phrase "shadow fleet" refers to ageing oil tankers operating under false flags to bypass Western sanctions on Russian, Iranian and Venezuelan crude, per France 24. There is no official definition. Analysts also call them the dark fleet, the ghost fleet or the parallel fleet, and the terms are used inconsistently enough that experts routinely talk past each other. The most useful working definition, per the European Parliament, is broad: vessels lacking Western insurance and belonging to non-EU/G7+ companies.^[2][12][13]

How a Tanker Disappears

The mechanics are less exotic than the name suggests. The most common tactic is "going dark" — switching off or manipulating the Automatic Identification System, the transponder that broadcasts a ship's identity and position. AIS is voluntary, which means a vessel can simply vanish from commercial tracking screens when it has something to hide. Vessels also broadcast fake location signals or carry out ship-to-ship transfers under cover of darkness, per France 24. The IMO acknowledged as far back as 2013 that high-seas ship-to-ship transfers were high-risk activities undermining the international regime on maritime safety, environmental protection and liability.^[2][3][11]

Then there is identity itself. Vessel identity laundering exploits flaws in the IMO numbering system to create a complete shell identity, according to Wikipedia's summary of the practice. Operators falsify registration details; ships change flags, often to countries unable or unwilling to enforce Western sanctions. By 2025, the number of falsely flagged ships worldwide had more than doubled to over 450, per France 24. A vessel removed for sanctions violations can re-register under another state within days, according to RUSI.^[2][3][10]

The Flag Business, Explained

Every merchant ship must register in a country — its flag state — which is legally required to inspect the vessel regularly, certify equipment and crew, and issue safety and pollution-prevention documents. That is the theory. In practice, flags of convenience let owners register in a country other than their own, often to escape stricter safety standards at home. The modern practice began in the 1920s, when U.S. shipowners wanting to serve alcohol during Prohibition registered their vessels in Panama. As of 2025, more than half the world's merchant tonnage sails under open registries, and five flag states — Panama, Liberia, the Marshall Islands, Hong Kong and Singapore — control 77 percent of flag-of-convenience vessels.^[7][9]

The problem is not flags as such. It is what minimal due diligence allows. Numerous flag states permit registration without verifying beneficial ownership or assessing sanctions risk, per RUSI, and private registration services operate with little oversight, often outside the territory of the flag state they represent. Gabon reportedly more than doubled its ship registry in 2023; roughly 98 percent of its tankers are classified as high-risk, with no identifiable owners, according to Reinsurance News. Anonymity is the product.^[4][10]

"In many cases, identifying the owner of a vessel is impossible." — on the core flaw of flag-of-convenience registries.

The Insurance Gap Nobody Wants to Underwrite

Western protection-and-indemnity clubs — the mutual insurers that cover third-party liability for roughly 87 percent of the world's ocean-going tonnage, per the International Group of P&I Clubs — largely withdrew from underwriting sanctioned oil shipments. The International Group estimates around 800 tankers have left its clubs as a direct result of the oil price cap. Into that gap stepped a handful of Russian insurers offering hull and liability cover, P&I-style services, or at minimum the documentation ports and brokers need to process a voyage, according to Reinsurance News.^[4][6]

The result is a two-tier insurance market. Clubs that remain in the International Group apply extensive due diligence and will terminate a contract or invoke a cesser clause if a member breaches sanctions, per the Group's written evidence to a UK parliamentary committee. The Swedish Club, for its part, states it is legally obliged to screen sanctions when selling lead-basis cover for a voyage to a high-risk country — but cannot perform due diligence on behalf of members, who must do their own. It also notes a blunt asymmetry: a voyage may be lawful for the member but not for the club to insure. And its service level can be constrained by the risk appetite of banks and reinsurers — what it calls the "Extended Enterprise."^[5][6]

The Tier 1 attestation at the heart of the price cap is, per the International Group, merely a self-declaration signed by traders that the sale price complies. The Group concludes the cap "appears increasingly unenforceable as more ships and associated services move into this parallel trade."^[6]

Who Pays When a Rusting Hull Runs Aground

The fleet is structurally old: 96 percent of crude tankers and 92 percent of product tankers in the shadow fleet are older than fifteen years, per the Geopolitics and Security Studies Center. Many operate under complex chains of beneficial ownership and shell companies — a model that reduces compliance scrutiny and increases the likelihood of underinsurance or disputed claims, according to Reinsurance News. The risks, per the Atlantic Council, include collisions and other accidents, spills of oil and hazardous substances, and a broader threat to maritime order when a significant minority of ships stop upholding the rules.^[4][12][14]

Who bears those risks? Coastal states with weaker enforcement, crews on uninsured vessels, and — indirectly — everyone else. The 1978 sinking of the Amoco Cadiz, which flew the Liberian flag, spurred an entire new category of maritime enforcement; the current fleet is larger, older and harder to identify.^[7][12]

The Enforcement Squeeze — and Its Limits

Governments have responded with targeted vessel designations and expanded collaboration, per the European Parliament. In October 2024, MEPs called for enhanced maritime surveillance, tighter shipping controls and broader sanctions. The U.S. Senate passed the Sanctioning of Russia Act of 2026, which targets major purchases of Russian energy and broadens enforcement beyond the vessels themselves, per the American Action Forum. As of February–March 2026, 623 oil tankers had been designated by at least one sanctions regime — yet 111 of them continued loading Russian oil cargoes, per the GSSC.^[11][13][14]

The gaps are structural. Current governance tools under the International Maritime Organization lack enforcement power and do not address the underlying regulatory failures, per RUSI. The IMO only defined the term "dark ship" in a resolution in October 2023 — two decades after North Korea and Iran began using shadow fleets to evade UN sanctions, and more than a year after Russia's full-scale invasion of Ukraine triggered the current expansion.^[3][10]

Reported with AI assistance using internet sources.