The sanctioned Chinese oil and gas tanker Rich Starry concealed its precise location in the Persian Gulf for more than ten days before trying to leave via the Strait of Hormuz this week. When the ship entered the Gulf of Oman, the waters near where the U.S. Navy was conducting a blockade of Iranian ports, it suddenly turned around and turned back. The ship anchored off the coast of Iran on Wednesday.
U.S. President Donald Trump ordered the U.S. Navy to begin a blockade of Iranian ports on Monday in an effort to force Iran to reopen the Strait of Hormuz.
The vessel's movements, tracked by shipping data companies and analysts, point to a cat-and-mouse game between the so-called "shadow fleet" of tankers and U.S. forces blockading Iran's coast on orders from President Trump.
According to shipping database Equasis, the Fortune Star has changed its name twice in its 11 years of operation. Such vessels are part of a gray shipping network that helps Iran circumvent sanctions, including on its oil industry. There are early signs that, after years of successfully circumventing restrictions, Iran's shadow fleet now appears to have met its match under a U.S. naval blockade - its ships are now having difficulty sailing out of the Persian Gulf.
This fleet, formed by Iran, Russia and Venezuela, uses a variety of means to avoid tracking: including turning off the transponder system that broadcasts the identity and location of the ship, "lost sailing", or sending false position signals for signal forgery. Iranian ships also conduct ship-to-ship crude oil transfers at sea to conceal the origin of the cargo.
"They are veterans at evading tracking," said Bridget Diaquin, senior risk compliance analyst at Lloyd's List Intelligence, a shipping analyst firm. "It's not one or two ships that are doing this, it's a large number of ships."
The U.S. military began blocking all ships entering and leaving Iranian ports on Monday in an apparent effort to pressure Iran to reopen the Strait of Hormuz waterway, which is vital to global shipping, and eliminate tolls.
The US military stated that it did not target all sanctioned ships, but only intercepted ships leaving Iranian ports. But the Fortune Star, which was sanctioned by the U.S. Treasury Department for carrying Iran-related goods, highlights the complexity of identifying which ships may be carrying Iranian goods. Over the past week, the ship was reported to be lingering off the coast of the United Arab Emirates, shipping data firm Kpler showed. Lowe's intelligence analysts combined advanced data analysis with human intelligence screening and said this was a fake trail. They found that the Fortune Star faked signals for more than ten days until it tried to sail out of the Persian Gulf on Tuesday, during which time it had the opportunity to load Iranian petroleum products.
The United States will have to rely on intelligence, satellite and tracking data, as well as drones and radio communications with crews to identify potential blockade-breaking ships. According to reports, the United States has deployed more than 15 warships to carry out blockade tasks. Officials said that deploying ships along the coast of Iran may put U.S. military facilities at risk of attack, so the U.S. will most likely intercept or control commercial ships in the Arabian Sea.
On Wednesday, U.S. Central Command, which oversees U.S. military operations in the Middle East, said no ships had breached the blockade in the 48 hours after it was launched. A total of nine ships followed U.S. military orders to turn around and reenter Iranian ports on the Gulf of Oman coast.
At least 10 ships passed through the Strait of Hormuz on Tuesday, some with characteristics of shadow fleet activity, shipping analysts said, according to Lloyd's List intelligence data. A Panamanian-flagged bulk carrier, the Manali, sailed out of the Persian Gulf on Monday and declared its destination to be a port in the United Arab Emirates. Diaquin said the ship had falsified location records and was therefore classified as a member of the shadow fleet.
Until now, it has been far less difficult for Iran-linked ships to sail into the Persian Gulf than out, perhaps reflecting the difficulty U.S. forces have in judging a vessel's heading before it arrives. Lloyd's List Intelligence said the sanctioned container ships "Rayen" and "Daisy" entered the Strait of Hormuz on Tuesday and were heading to Iran's Bandar Abbas Port.
Military and shipping analysts said these developments indicate that shadow fleet operators are trying to test the bottom line of the blockade and whether the United States will take action to enforce the blockade.
Brian Clark, a former senior official of the U.S. Navy and now a senior fellow at the Hudson Institute, said: "I think they are testing the bottom line to see if the United States will really implement a full blockade."
The shadow fleet first appeared in 2012 after the United States tightened sanctions on Iran and was used to transport Iranian oil; after Trump imposed new sanctions on Iranian crude oil sales in 2018, the size of the fleet further expanded; after the outbreak of the Russia-Ukraine conflict in 2022, the fleet expanded significantly again in order to undertake Russia's huge oil exports.
According to data from the shipping tracking website TankerTrackers.com, the global shadow fleet has reached nearly 1,500 ships, most of which are circulating among multiple sanctioned markets. Samir Madani, co-founder of the website, which uses satellite imagery to locate ships, said more than 600 of them had transported Iranian oil, including about 60 tankers in Iran's state-owned fleet. He said that under years of severe sanctions, shadow ships serving Iran often used false data trajectories to pretend to depart from Iraqi or Saudi ports.
Kevin Rowlands of the Royal United Services Defense Institute in London said that by integrating ship signals, satellite and patrol aircraft images, and intelligence collection information, the United States should be able to quickly determine whether a ship has sailed out of the Strait of Hormuz from an Iranian port.
Rowlands added that the biggest question is where the U.S. military will take the ships it inspects. Earlier this year, the US military docked a shadow tanker tracked from Venezuela at a British port, but he said that he was currently unaware of any relevant agreement between the US and Gulf countries to reach a similar arrangement.
Rowlands said that if a ship claims to be heading to a non-Iranian port, it will be more difficult for the United States to promptly determine its destination after entering the Persian Gulf and seize it.
Steven Wells, a naval expert at the Washington Maritime Strategy Center and a former active-duty officer of the U.S. Navy, said that at least since World War I, ships stopping at multiple ports have caused problems for maritime blockade law enforcement. He said the U.S. military will use drones and other intelligence methods to mark, track and eventually intercept ships leaving Iranian ports.
"How many ships will test the blockade? Does the Navy have enough ships, aircraft and equipment to respond?" Wells said.