77 Ships Blacklisted, None Deterred: Inside Iran’s Failing Hormuz Toll Regime

At a Glance

• All 77 vessels blacklisted by Iran’s Persian Gulf Strait Authority used the “unauthorized” southern corridor through Omani waters or transited Iran’s northern corridor without paying tolls.
• Inclusion on the list does not appear to have prevented ships from continuing to trade in the region.
• 85% of blacklisted ships were tankers, reflecting their disproportionate use of the U.S. military-assisted southern corridor.
• Liberia-flagged ships are disproportionately targeted at 38% of the list, with Panama and Barbados next at 6% each.
• Vessels owned or chartered by Emirati companies dominate at 40%, followed by Greece at 12% and South Korea at 9%.
• Sinokor Marine, which shipped 40% of all crude via Hormuz over July, had at least eight tankers blacklisted, alongside tankers owned by Saudi national carrier Bahri.
• Only 35% of blacklisted ships broadcast their location in the two days to September 16, and only six transmitted AIS west of Hormuz in the past seven days.
• Nearly all vessels on the list carry International Group P&I cover, which is prohibited from insuring ships that pay tolls to Iran.

Operational Overview

Iran’s Persian Gulf Strait Authority opened in mid-May to oversee transits and toll payments through the Strait of Hormuz. It has since released three tranches of blacklisted vessel names, on August 24, September 2, and September 14. Windward analysis of all 77 vessels finds that every one used the “unauthorized” southern corridor through Omani waters or transited Iran’s northern corridor without paying any tolls.

The list is highly targeted and punitive, aimed at ships deemed to have undermined Iran’s control over the Strait by not seeking Iranian permission to transit. Based on the selection criteria, any vessel using the southern corridor could be placed on the list, as could ships using Iran’s northern corridor with marine insurance linked to Western providers.

Inclusion on the list does not appear to have prevented ships from continuing to trade in the region.

When adding further vessels to the list on September 14, the Persian Gulf Strait Authority directly referenced classification societies and marine insurers, saying they needed to protect against the consequences arising from dealing with these vessels. Nearly all but six of the blacklisted vessels were assessed as having P&I cover with the International Group of 12 P&I Clubs, which are prohibited from insuring ships that pay tolls to Iran.

Tankers Dominate the List

85% of blacklisted ships were tankers. This reflects their disproportionate use of the U.S. military-assisted southern corridor to ship oil exports from Gulf energy companies to market.

While the average number of reported U.S.-facilitated transits through the corridor brings total transits to 16% of pre-war levels, crude volumes excluding Iran moving through Hormuz over August were assessed by Windward at 45% of pre-war levels.

Liberia-Flagged Ships Are Disproportionately Targeted

38% of blacklisted vessels were Liberia-flagged, totaling 30 ships. The next most targeted flags were Panama and Barbados, at 6% each.

This reflects Liberia’s position as the flag of choice for ships owned by companies including ADNOC and Sinokor Marine that dominate Hormuz tanker transits via the southern corridor.

Emirati-Linked Vessels Dominate Ownership

Vessels owned or chartered by companies in the UAE dominate the list, at 40% of blacklisted ships. The second-largest country of commercial operators was Greece at 12%, followed by South Korea at 9%.

This underscores the UAE’s prominent role in using the southern corridor since May, when covert shipments began under U.S. military support and guidance. Since June, total UAE crude exports in August and September, via ship and pipeline, have equalled or surpassed pre-war levels according to Vortexa data. This reflects national oil company ADNOC’s willingness to pay high charter rates to secure tankers prepared to undertake shuttle transits via Hormuz to waters off Fujairah and Oman, transferring to tankers for onward shipment to Asia or India.

Greek shipowners comprised 12% of blacklisted vessels. A cohort of privately owned Greek operators have accepted the high premiums to undertake risky transits for national Gulf energy companies.

Sinokor Singled Out

Sinokor Marine, the South Korean shipowner that Windward analysis found shipped 40% of all crude via Hormuz over July, had at least eight tankers blacklisted. Tankers owned by Bahri, the Saudi national tanker company, were also listed.

Most Blacklisted Ships Are Running Dark

Most blacklisted ships have switched off AIS for safety and security reasons. 35% of blacklisted ships had broadcast their location in the past two days to September 16. 61% had broadcast AIS at some point over September, signalling most are still trading in the region but with AIS off.

Only six of the 77 ships transmitted AIS in areas west of Hormuz in the past seven days, Windward analysis shows.

The Cargo Ships on the List

Eight bulk carriers were included, among them two Greece-owned ships, MINOAN PIONEER (IMO 9471630) and MINOAN DIGNITY (IMO 9294484). Both were attacked by Iran after delivering agricultural products to Iran’s Bandar Imam Khomeini port.

MINOAN PIONEER had transited via Iran’s northern corridor with its AIS on, on July 29. MINOAN DIGNITY was attacked in August while dark and using the southern corridor.

In all cases, blacklisted vessels using the northern corridor were insured with International Group P&I providers, which are prohibited from insuring ships that pay tolls to Iran.

Anomalies in the Data

Three entries on the list stand out.

One vessel, BANASTAR (IMO 9228045), had not transited Hormuz since the war began. This may be an IMO numbering error.

One Aframax tanker, RIESCO (IMO 9251822), was sanctioned by the U.S. and falsely flagged with Zimbabwe. It was one of five vessels destroyed by CENTCOM on September 8.

CENTCOM forces destroyed five Iranian crude oil carriers, Sept. 8, after the Islamic Revolutionary Guard Corps (IRGC) targeted a U.S. Navy warship with ballistic missiles twice over the past two days. The U.S. warship successfully evaded the attempted Iranian attacks and… pic.twitter.com/Gi8a2tloN1

— U.S. Central Command (@CENTCOM) September 8, 2026

Two service vessels, both falsely flagged, were also included. Both were assessed by Windward as using the southern corridor.

Outlook

Iran’s Persian Gulf Strait Authority opened in mid-May to oversee transits and toll payments through Hormuz and has since published three tranches of blacklisted vessel names. Every vessel on the list either used the southern corridor or crossed Iran’s northern corridor without paying tolls, and inclusion has not prevented ships from continuing to trade in the region.

The composition of the list is weighted toward tankers at 85%, Liberia-flagged hulls at 38%, Emirati-linked owners at 40%, and Sinokor with at least eight vessels named.

When adding further vessels on September 14, the Persian Gulf Strait Authority directly referenced classification societies and marine insurers, saying they needed to protect against the consequences arising from dealing with these vessels. Nearly all but six of the blacklisted vessels were assessed as having P&I cover with the International Group of 12 P&I Clubs, which are prohibited from insuring ships that pay tolls to Iran.