Bloomberg: Nearly Quarter of Stranded Oil Tankers Secretly Crossed Strait of Hormuz

Nearly one-quarter of the large non-Iranian oil tankers stranded in the Persian Gulf since the outbreak of hostilities involving Iran and the closure of the Strait of Hormuz have managed to make covert crossings through the strategic waterway, according to data compiled by Bloomberg.

The analysis found that 29 of the 109 tankers trapped in the Gulf since the conflict began on February 28 successfully navigated the strait despite mounting security risks and operational restrictions. Each of the vessels carries at least 700,000 barrels of crude oil or petroleum products, highlighting the significance of the movements for global energy markets.

Although the cargoes transported by the vessels that have escaped represent only a fraction of the oil and fuel supplies still stranded in the Gulf, traders have absorbed the shipments rapidly amid a historically sharp decline in global petroleum inventories.

Market observers believe the actual number of successful crossings may be considerably higher. Many vessels operating in the region have reportedly switched off their automatic identification systems (AIS), which transmit location data and allow ships to be tracked by maritime authorities and commercial monitoring services.

As intermittent hostilities between the United States and Iran continue into their third month, shipping companies have increasingly relied on unconventional navigation strategies to move cargo through one of the world's most important energy chokepoints.

According to shipping and industry sources cited in the data, some tankers crossed the Strait of Hormuz under conditions of secrecy, while governments whose economies depend on the shipments were compelled to engage in diplomatic efforts to secure Iranian approval for the passage of certain cargoes.

The Bloomberg assessment excluded vessels linked to Iran from its calculations. Iranian-affiliated ships reportedly continued to enjoy freedom of navigation through the strait until mid-April, when U.S. President Donald Trump ordered a maritime blockade targeting Iranian ports, aimed at preventing vessels from entering or leaving Iranian terminals.

Tracking Iranian oil exports has become increasingly difficult in recent years. Even before the latest conflict erupted, many Iranian-linked vessels routinely operated without transmitting location signals in Gulf waters, limiting visibility into the country's crude oil movements.

The Strait of Hormuz remains one of the world's most strategically important maritime corridors, serving as a critical route for a substantial share of globally traded oil. Any disruption to traffic through the narrow passage has immediate implications for energy prices, shipping costs, and international supply chains.

With large volumes of crude still stranded and regional tensions showing few signs of easing, energy markets continue to closely monitor tanker movements and diplomatic developments across the Gulf.