Iran briefly opens, then closes Strait of Hormuz, affecting ship movement

Iran briefly opened the Strait of Hormuz on Saturday before closing it, affecting ship movement. The market on the UK sending warships through the strait by April 30 sits at 7.5% YES, down from 12% a week ago.

Market reaction

The brief opening allowed 12 ships to exit and 3 to enter before Iran’s warning led to 9 tankers and 4 container ships reversing course. The UK warship market has not moved in response to the volatile situation. Daily USDC volume is $2,086, with just $427 needed to move the odds 5 percentage points, which makes this a thin market vulnerable to large orders. The largest price move was a 1-point drop, suggesting limited conviction in a UK naval response. Explore the market.

Why it matters

About a fifth of global oil passes through the Strait of Hormuz, so Iran’s ability to open and close it at will raises the question of whether the UK or allied navies will respond with force. But the odds dropping from 12% to 5.5% over the past week suggest traders see the UK as less likely to act, not more, even as the situation on the water gets worse.

What to watch

At 6¢, a YES share pays $1 if warships transit, a 16.7x return. For that bet to make sense, you’d need to believe the UK sees an urgent need to protect shipping lanes in the next 14 days. Watch for announcements from the UK Ministry of Defence or any allied naval movements that could shift perceptions. The contract expires April 30.

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