Clandestine oil shipments sailing without transponder signals through the Strait of Hormuz have helped ease a global crude shortage, yet persistent uncertainty over exact export volumes has driven international oil prices higher, according to market data analyzed by Reuters.
Crude Flows and the ‘Dark Crossing’ Phenomenon
Tankers carrying Middle Eastern crude have increasingly relied on “dark crossings” of the Strait of Hormuz, navigating without Automatic Identification System (AIS) transponder signals to avoid potential Iranian attacks. According to ship trackers, analysts, and trading sources cited by Reuters, this practice forms part of what is described as the world’s largest clandestine tanker operation, organized with U.S. military support. These covert voyages have allowed crude oil from Iraq, Kuwait, Qatar, Saudi Arabia, and the United Arab Emirates to keep reaching international markets.
Conflicting Export Estimates and Market Consensus
Estimates regarding the total volume of Middle Eastern crude reaching global markets have varied widely since maritime disruptions began following U.S.-Israeli attacks on Iran on February 28, according to Reuters reporting. While U.S. Data analyzed by Reuters shows that the broader industry consensus sits closer to two-thirds of pre-war volumes.
Similarly, London-based analytics company Vortexa estimated that total August oil exports from the Gulf reached 15 million bpd, leaving volumes down by 10 million bpd compared to pre-war levels. Vortexa also reported that crude and refined products moving through the Strait of Hormuz on a seven-day moving-average basis stood at roughly 8 million bpd. “Daily transits fluctuate strongly with substantial spikes and troughs,” said Vortexa analyst Pamela Munger, highlighting the volatility in regional maritime traffic.
Peak Flows Versus Sustained Export Realities
Market analysts also find there is a discrepancy between peak daily flows and sustained exports. Figures from Kpler and an industry source indicate that Gulf crude exports reached as much as 14 million bpd on some days in early September, combining secret tanker flows and Saudi Red Sea exports that avoid the Strait of Hormuz. However, depending on the intensity of Iran’s tanker attacks, on other days, exports were much lower. Calculations by Reuters—based on an average oil price of $80 per barrel and a conservative assumption of 6 million barrels, or six large tankers, a day over the last 90 days—suggest that dark shipments amounted to at least 500 million barrels in June to August, representing a value of at least $40 billion.
Did you know? That would be worth at least $40 billion.
Frequently Asked Questions
What are ‘dark crossings’ in the Strait of Hormuz?
Dark crossings mean tankers sail without transponder signals to avoid Iranian attacks, a clandestine operation organised with U.S. military support.
How much oil is still missing from the Gulf region?
Why are international oil prices rising?
Uncertainty over volumes has helped to drive oil prices higher, and uncertainty over their extent has added to the risk premium in international oil prices.
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