Hey,

In March 2026, tanker traffic through the Strait of Hormuz collapsed 93%. But it didn't go to zero. The vessels still transiting had one thing in common: they had nothing to lose. No Western insurance. No reputable flag. No AIS signal. Welcome to the dark fleet — the shadow system that runs beneath global shipping, and that nobody talks about until a crisis makes it impossible to ignore.

The dark fleet is not a single organization. It is not centrally controlled. It is a loose ecosystem of vessels, operators, shell companies, and financial networks that exists for one purpose: to move oil that the Western world — the US, EU and their allies — has decided shouldn't move.

Who composed it. Three sanctioned producers built the dark fleet into what it is today. Russia, following Western sanctions after the invasion of Ukraine in 2022, needed to move roughly 3 million barrels of crude per day outside the official Western system. Iran, under sanctions for decades, had already developed sophisticated evasion networks. Venezuela, cut off from U.S. markets, joined the same infrastructure. By late 2025, the dark fleet numbered more than 1,300 vessels — nearly one in every five oil tankers worldwide. It has more than tripled in size since 2022. Around it, a layer of opportunists: shipowners, brokers, and operators with no particular political allegiance who simply recognized that moving sanctioned oil at a discount generates significant margins for those willing to accept the risk.

How they operate. Four mechanisms define dark fleet operations. First, AIS manipulation — switching off the Automatic Identification System that allows vessels to be tracked, or broadcasting false locations. In 2025, 77% of vessels carrying sanctioned Iranian crude spoofed their location, and 72% turned off their tracking beacons for extended periods. Second, flags of convenience — registering under permissive jurisdictions with minimal oversight. Over 70% of sanctioned vessels changed flags at least once in 2025, cycling through registries in Gabon, the Cook Islands, Sierra Leone, Guinea-Bissau, and others. Third, ship-to-ship transfers — transferring cargo between vessels in international waters to obscure the origin of the oil. The barrel that left an Iranian terminal arrives at a Chinese refinery having changed hands twice at sea, with no paper trail connecting the two endpoints. Fourth, opaque insurance — operating without recognized P&I club coverage, using fake certificates, or relying on informal arrangements that would never pay out in the event of a major incident.

What it means for everyone else. The implications extend well beyond the sanctioned producers themselves. For the insurance market, dark fleet vessels represent a growing exposure — not through policies they hold, but through the collateral risk they create for legitimate shipping operating in the same waters. An uninsured tanker carrying 2 million barrels of crude, operated by a crew paid in cryptocurrency, sailing without functional safety systems, is an environmental catastrophe waiting to happen with no identifiable party to cover the damages. For ports and maritime authorities, the dark fleet creates enforcement challenges that the current legal framework is not equipped to handle. For legitimate shipping companies, it represents a competitor that operates without the cost base of compliance — no real insurance premiums, no sanctions screening, no ESG obligations.

The dark fleet is not an accident. It is the predictable consequence of two forces that the architects of Western sanctions did not fully account for.

The economic logic. When the price differential between sanctioned and non-sanctioned oil is large enough, there will always be operators willing to bridge the gap. Russian crude trades at a discount to Brent. Iranian crude trades at a deeper discount. Venezuelan crude is cheaper still. Chinese and Indian refiners, the primary buyers of sanctioned oil, capture that discount as margin. The operators who move the cargo extract a risk premium. At every step of the chain, someone is making money — and the combined financial incentive is large enough to sustain a fleet of over 1,300 vessels operating outside international norms. This is not ideology. It is arithmetic.

The sanctions paradox. Western sanctions were designed to isolate Russia, Iran, and Venezuela from global energy markets. What they actually did was create a parallel energy market — one that is less transparent, less regulated, and harder to monitor than the system it replaced. Before 2022, Russian oil moved on mainstream tankers through recognized channels. After 2022, it moved on aging vessels through opaque networks. The oil still moved. The difference is that now it moves in a way that generates less visibility, less accountability, and more risk for the global maritime system. The sanctions didn't stop the oil. They changed who moved it and how.

The Hormuz crisis has made this dynamic impossible to ignore. When Maersk, Hapag-Lloyd, MSC, and CMA CGM suspended transits in early March, the vessels that kept moving were almost exclusively dark fleet operators. Lloyd's List intelligence data showed that roughly half of all oil tankers transiting the Strait of Hormuz between March 1 and 8 were shadow fleet vessels. By March 31, AIS data showed that 36% of transits were on vessels under U.S. sanctions.

Iran has not simply closed the strait. It has established a selective, permission-based transit regime — controlling who can pass, via which route, and at what cost. The route now runs through Larak Island in Iranian territorial waters, where the IRGC exercises direct oversight. The vessels that qualify for passage under this system are, almost by definition, those that operate outside Western regulatory frameworks. The selective blockade of Hormuz is not just an act of war. It is a business model — one that monetizes Iran's control over the chokepoint while routing revenues to sanctioned actors.

The result is a situation where the world's most strategically important energy corridor is being managed, at least partially, by a fleet of aging, uninsured, untracked tankers operating under the oversight of Iran's Revolutionary Guard. That is not a temporary disruption. It is a structural shift in how a significant share of global energy trade operates.

The limits of maritime regulation. The dark fleet exposes a fundamental weakness in the international maritime governance system. The IMO sets standards. Flag states enforce them — or don't. Port State Control inspects vessels — when they call at ports. Insurance requirements exist — but fake certificates are easily produced. The entire system rests on the assumption that vessels want to participate in the regulated system because exclusion from it carries meaningful costs. The dark fleet has demonstrated that for a sufficiently motivated operator, exclusion from the Western maritime system is not a cost. It is a business model. That realization has no easy regulatory fix.

The erosion of sanctions as a geopolitical tool. If the dark fleet can move Russian, Iranian, and Venezuelan oil at scale — and the evidence strongly suggests it can — then oil sanctions are not a reliable instrument of geopolitical pressure. They are a tax on the sanctioned country's energy revenues, not a prohibition on those revenues. Russia has lost margin on every barrel. Iran has lost margin on every barrel. But both continue to export at volumes that have surprised Western analysts. The dark fleet is the infrastructure that makes that possible — and its existence fundamentally changes the calculus of what sanctions can and cannot achieve.

Western governments are beginning to respond. Since December 2025, U.S., EU, and Indian authorities have seized or detained at least 14 dark fleet vessels. Belgium and France have conducted joint boarding operations. The UK has announced that its armed forces can board Russian shadow fleet vessels in British waters. But the scale of the response remains far smaller than the scale of the problem. Over 1,300 vessels. An estimated 120 expected to reflag to Russia in the coming months. A financial infrastructure that spans cryptocurrency payments, shell companies in multiple jurisdictions, and crewing networks that span the globe.

Once you understand how the dark fleet works, you cannot unsee it. Every time you read about oil prices, about sanctions, about the Hormuz crisis — there is a layer of the story that the mainstream narrative doesn't capture. Who is actually moving that oil? Under what flag? With what insurance? With whose money?

The maritime industry has always operated with a degree of opacity that other sectors don't. That opacity has costs — environmental, geopolitical, and financial — that are distributed across the entire global economy without most people realizing it.

Sunday Compass exists precisely for this. Not to give you the news you can find anywhere, but to give you the framework to understand what's actually happening beneath the surface — in an industry that moves 90% of everything the world trades, and that most people never think about until a crisis makes it impossible to ignore.

Now you know. And that knowledge is worth something.

Talk soon,

Fer

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