Iran's Persian Gulf Strait Authority (PGSA, the Iranian maritime body administering the toll architecture) published the formal coordinates of its "controlled maritime zone" on Wednesday 20 May1. The eastern boundary runs from Kuh-e Mubarak on the Iranian coast to southern Fujairah in the UAE; the western boundary runs from the tip of Qeshm Island in Iran to Umm Al-Quwain in the UAE. All vessels inside the zone, per the Iran International notice, must coordinate with the authority and obtain authorisation. PGSA has opened its vessel-submission portal four days earlier and is still withholding the fee schedule it promised.
The coordinates convert what had been operational practice and the Majlis's earlier toll bill into a cartographic-legal claim. Verbal declarations of authority can be walked back; published coordinates cannot, because they trigger a written obligation on neighbours and flag states. The United Arab Emirates has not, as of writing, published a counter-coordinate set, which leaves Emirati silence as a maritime-law response.
The insurance consequence runs through Lloyd's of London. Until Wednesday, underwriters had a verbal toll claim and a portal whose fee schedule remained unwritten. With coordinates on a chart, the boundary can be modelled: tanker routes can be plotted against the zone, war-risk premium tiers can be drawn against entry and exit lines, and the structural insurance layer Goldman Sachs and Morgan Stanley flagged on 12 May now has the cartographic input it needs to price.
Tehran chose to publish coordinates while withholding the fee, and the asymmetry reads as deliberate. The chart converts the zone into a legal fact; the missing fee preserves Iranian discretion over what compliance actually costs. Flag states and underwriters now have to accept or reject the cartography on paper, while Tehran retains the room to set the price later.
