Why this matters for Europe: Europe's inflation and supply exposure depends on how much Gulf oil is actually reaching world markets. The newest evidence shows why vessel counts alone cannot answer that.
OilWatch Network Analysis — visible traffic has nearly stopped, yet the barrels have not. What that gap does and does not tell us.
Shipping through the Strait of Hormuz appeared to approach a standstill over the weekend.
Kpler recorded five commodity-vessel transits on Saturday and none on Sunday, compared with 31 during the preceding weekend. Before the Iran war, more than 130 vessels of all types crossed the Strait each day.
Taken literally, those figures suggest that one of the world's most important energy routes has almost ceased functioning. Yet oil continues to reach tankers waiting outside the Gulf, and Brent has remained around $80–$90 rather than approaching the $150 levels feared at the beginning of the conflict.
The explanation is not that Hormuz has reopened. It is that part of the trade has gone dark.
Our earlier analysis described the reported traffic as an AIS-observed floor. The new reporting helps explain the mechanism behind that floor.
The visible traffic is genuinely collapsing
The weekend figures describe vessels that commercial tracking systems could identify crossing the Strait. They are therefore important — but they are not a complete count of the oil being moved.
Among the vessels Kpler identified was an empty VLCC whose AIS was switched off, an Indian gas carrier entering by the route controlled by Iran, and a small tanker carrying Iranian fuel oil out of the Gulf.
The presence of an AIS-dark vessel inside such a small observed group is itself evidence of the measurement problem. Ships are switching off or manipulating their tracking signals to reduce their exposure to attack, interception or identification.
Nevertheless, the decline in visible traffic is real. Five commodity vessels on Saturday and none on Sunday represents a sharp deterioration from the previous weekend. It followed three reported attacks on ADNOC-operated vessels within a week. Reuters' account of the weekend traffic makes clear that normal commercial passage has not resumed.
Missing ships do not necessarily mean missing barrels
A separate Bloomberg investigation reports that Gulf producers are operating an extensive covert shuttle system.
Smaller or specially designated vessels load inside the Persian Gulf, cross Hormuz with little or no usable tracking signal, and transfer their cargoes to larger tankers waiting in the Gulf of Oman. Those receiving vessels can then carry the oil to customers without having entered the most dangerous part of the route.
According to Bloomberg's sources, these shuttle movements are carrying more than the market's approximate estimate of four million barrels per day. Around 150 vessels were reportedly gathered outside Oman, compared with approximately 40 in January, many waiting to receive transferred cargoes.
The operating method is credible and independently corroborated. Kpler reported in July that the UAE had returned to exports above three million barrels per day by combining its ADCOP pipeline to Fujairah with Hormuz shuttle voyages and ship-to-ship transfers in the Gulf of Oman. Kpler's July assessment confirms the mechanism, even though it does not verify Bloomberg's latest aggregate estimate.
This means that ordinary AIS counts are now systematically understating activity. It does not mean that every missing vessel can be converted into a known quantity of oil.
Four different numbers are being confused
The apparent contradiction largely disappears once the measurements are separated.
The first number is the visible vessel count. This measures ships that tracking systems can identify crossing the Strait. It includes different vessel types, directions and cargo states. An empty tanker entering the Gulf counts as one vessel but carries no exported oil.
The second is estimated crude throughput through Hormuz. Kpler estimated crude exports at 2.77 million barrels per day during the week beginning 27 July and 1.74 million during the week beginning 3 August. Its highest post-war weekly figure was 6.98 million barrels per day.
The third is total Middle Eastern exports. This is a wider measure that includes oil leaving through Saudi Arabia's Red Sea terminals, the UAE's Fujairah facilities and other routes that bypass Hormuz. Kpler estimated 9.53 million barrels per day during the week beginning 3 August and a four-week average of 12.26 million. LSEG estimated 9.33 million barrels per day during the first 12 days of August.
The fourth is the US government's claim. Energy Secretary Chris Wright said that almost nine million barrels per day were leaving through Hormuz, with another five to seven million using pipelines and alternative export facilities. That would put total regional flows at approximately 15 million barrels per day.
The independently tracked figures remain between three million and five million barrels per day below that claim. Reuters' comparison of the estimates concluded that clandestine voyages could explain some of the discrepancy, but that double-counting ship-to-ship transfers is another plausible explanation.
Until the US releases vessel and cargo details, its nine-million-barrel Hormuz figure should be treated as an attributed government claim rather than an established measurement.
The shuttle volumes cannot simply be added
The same oil can appear several times in maritime data.
A cargo may cross Hormuz aboard a dark shuttle vessel, be transferred outside Oman, depart again aboard a larger tanker and eventually appear in an Asian port's import figures.
Those are four observations of one cargo — not four separate quantities of oil.
This is especially important when combining Bloomberg's shuttle estimate with commercial tracking totals. Kpler, Vortexa and LSEG may already reconstruct some dark voyages using satellite imagery, draught changes, port activity and subsequent ship-to-ship transfers. Adding the reported shuttle volume to their export estimates could therefore count some barrels twice.
Other figures in the report require similar care.
ADNOC's reported sale of approximately 135 million barrels describes commercial commitments. It does not prove that all those barrels have crossed Hormuz or reached their customers.
Likewise, approximately 150 ships gathered outside Oman demonstrate the scale of the logistics operation, congestion and available transfer capacity. They do not constitute a daily flow measurement.
Destination data has not settled the question
Oil arriving at destination ports provides the best eventual check because a barrel discharged in China, India, Japan or South Korea cannot remain hidden indefinitely.
Kpler recorded Middle Eastern crude arrivals of 13.27 million barrels per day in July, including 10.86 million discharged in Asia. That was a substantial recovery from April, but it remained well below the pre-war average of 18.71 million barrels per day.
Much of July's increase also reflected vessels that escaped during the temporary June ceasefire. It cannot confirm how much oil is currently crossing under the newer covert arrangements.
China's total crude imports were 8.41 million barrels per day in July, more than three million below pre-war levels. Chinese refiners compensated by reducing processing and refined-product exports rather than relying entirely on inventories. Kpler currently estimates Chinese seaborne arrivals at about seven million barrels per day in August, compared with 11.52 million before the conflict. Reuters' examination of China's July balance therefore supports substantial continuing disruption.
Asian refiners are also buying more American and West African crude for delivery later in the year. US crude shipments to Asia reached a record 2.35 million barrels per day in July. That purchasing behaviour would be difficult to reconcile with a fully restored Middle Eastern supply system. Reuters reported the alternative purchases on 14 August.
The August claims should become testable through destination arrivals during September.
Why prices have not risen further
Covert Gulf shipments are helping to prevent a more severe supply shock, but they are only one part of the explanation.
Pipeline bypasses, emergency stock releases, lower refinery processing, reduced fuel exports and substitution with Atlantic Basin crude have all limited the immediate shortage. Demand has adjusted alongside supply.
Brent traded around $89 on Monday, having gained about 6% over the preceding week following attacks on tankers and Saudi infrastructure. Reuters attributed the limited further increase to the absence of a newly documented major supply outage — not to proof that Hormuz had returned to normal. Reuters' market report records both the renewed risk premium and the market's continued dependence on mitigating flows.
Price action must therefore be interpreted carefully. Oil remaining below the most extreme forecasts does not prove that the security mechanism has stopped operating. It shows that markets are pricing the disruption together with the workarounds.
The conclusion
The Strait of Hormuz has not reopened in any conventional sense.
Visible commercial traffic has deteriorated sharply, vessels continue to face attack, and normal insured shipping remains severely constrained. What has emerged instead is a hazardous parallel system of dark shuttle voyages, ship-to-ship transfers, pipeline bypasses and offshore loading operations.
That system is moving enough oil to soften the global price impact. It may also explain part of the gap between visible tracking and government estimates.
But the evidence does not yet validate the claim that almost nine million barrels per day are crossing Hormuz, nor does it demonstrate that regional exports have recovered to approximately 15 million barrels per day.
The best description is therefore not that Hormuz has reopened.
It is that the oil trade has adapted by becoming harder to see — and much more dangerous to operate.