By Lex Harvey, CNN
(CNN) — Some people watch Netflix in their spare time. Remy Osman tracks rusty tankers transporting illicit oil through one of the world’s busiest shipping lanes.
From the roof of his Singapore apartment building, the British expat, who works as a food and beverage salesman, documents the passage of these shadow vessels, often sanctioned by the US and other Western countries, for his growing online audience.
Shadow fleets, also known as ghost or dark fleets, are ships that use murky tactics to transport oil for pariah states like Russia, Iran and Venezuela. Oil revenues from these fleets, consisting of aging tankers with opaque ownership, have become crucial sources of funding for Russia’s war in Ukraine.
The US has cracked down on shadow fleets in recent months, seizing five sanctioned vessels as part of President Donald Trump’s pressure campaign against Venezuela and its now-ousted leader Nicolás Maduro, who was captured by US forces earlier this month.
In the waters off Singapore, the underground industry comes into public view.
The Singapore Strait is a crucial maritime shipping route connecting the Indian Ocean and the South China Sea. Roughly 100,000 ships pass through these waters each year, together carrying roughly one third of all goods traded globally.
The strait’s strategic location also makes it a hub for shadow fleets transiting between Iran, Russia and Venezuela to China, one of the world’s largest importers of sanctioned oil.
Osman has a front-row seat.
“Singapore is probably the best place on earth to see (shadow ships),” the 32-year-old said.
While ships above a certain size are required under international law to keep their automatic identification system (AIS) trackers on, shadow vessels will sometimes go dark to evade authorities. But because the Singapore Strait is so narrow, it’s practically impossible for a ship to transit safely without switching on its location tracker.
The strait is also so physically close to Singapore, a dense city home to roughly six million people, that Osman can see passing vessels and take photos or videos of them with just an iPhone.
Shadow fleet balloons
Since Russia’s invasion of Ukraine and the subsequent Western sanctions on Russian oil, the global shadow fleet has ballooned. While the deceptive tactics of the ships make them hard to track, data and analytics firm Kpler estimated the global shadow fleet comprised about 3,300 vessels in December 2025, representing about 6-7% of global crude flows.
The fleet is sustained through tactics such as fragmented ownership, rapid and repeated flag changes, manipulating location data, and shifting cargo at sea during the night or in areas with minimal oversight.
More than $100 billion worth of crude oil was moved through shadow and sanctioned fleets in 2025, according to Kpler.
Osman’s niche hobby began during the Covid-19 pandemic, when he was forced to quarantine for two weeks after moving to Singapore. He began spotting ships from his hotel room’s balcony and documenting their passage online.
It wasn’t until about a year ago that Osman shifted his focus to shadow vessels, after he noticed his audience was curious about the clandestine fleets. He says his page has exploded in recent months as shadow fleets have captured the news cycle.