Attacks on vessels near Hormuz reached a weekly record. Polymarket's contract on Washington officially ending its naval blockade of Iranian shipping by Oct. 31 slipped to 4.5 cents as sanctions tightened and no U.S. decision came.
Traders are steadily giving up on a quick policy reversal from Washington, one cent at a time.
Polymarket's contract on whether the U.S. government officially announces an end to its naval blockade of Iranian ships and the ships of Iran's customers by Oct. 31 traded at 6.5 cents at 4 p.m. Eastern on Thursday. It slipped to 5.5 cents in the evening and to 4.5 cents from 1 a.m. Friday onward. A two-cent move sounds small; it is nearly a third of the contract's value.
The contract pays only on an official U.S. announcement that ends, lifts or suspends the blockade. Partial exemptions and informal remarks do not count. It is a bet on a decision in Washington, not on traffic through the Strait. The market is thin, and each move is a single tick, but the direction has been consistent.
The backdrop at sea
The British military's maritime agency received 12 reports of attacks on vessels in the region between Oct. 5 and Oct. 11, the most in any week since the U.S.-Israeli war with Iran began. The prior week had 10. Six came on a single day, Oct. 11, also a high.
Iranian state media said a second tanker caught fire in the eastern part of the Strait after entering what it called a prohibited zone with its tracking systems disabled. The vessel's name, flag and the cause of the fire have not been confirmed. The commander of the Revolutionary Guards' navy said all ships "must obtain permission" to transit.
Washington's signals
None of the week's U.S. statements pointed toward lifting the blockade. President Trump said he would not use nuclear weapons on Iran and has no plans to deploy ground troops there, and no decision on new military action was announced.
The Treasury moved the other way on the financial side, designating an Iraqi bank and offshore networks it said support Iran. "The noose is tightening around Iran's economy," Treasury Secretary Scott Bessent said. An administration adding sanctions is not one preparing to announce an end to a blockade, which is consistent with the contract's slide.
In a separate Polymarket contract tied to the U.S. refraining from strikes on Yemen through Oct. 31, the price edged up to 91.5 cents from 90.5. Houthi missiles struck a presidential palace in Aden on Thursday, killing five people, according to Yemen's health minister, but the U.S. is not a party to the Saudi-Houthi exchange.
What the price says
At 4.5 cents, the market assigns roughly a 1-in-22 chance that Washington formally ends the blockade within two weeks. That is a market-implied figure, not an objective probability.
Market implications
One reading is that traders are rationally pricing a long standoff. Sanctions are tightening, attacks at sea are rising, and nothing in the week's U.S. statements suggests a decision to lift the blockade is near.
A second reading is that the low price leaves room for surprise. Trump has said the U.S. is negotiating with Iran, and an agreement that included an end to the blockade would reprice the contract many times over. At 4.5 cents, a small amount of new information could move it sharply.
What to watch
Any U.S.-Iran contact or statement on the blockade's terms, further Treasury actions, and weekly attack counts at sea. A move back above 6.5 cents would be the first sign that traders see a path to a U.S. announcement this month.