Saudi Arabia military action against Yemen on September 28?
The move lacks solid trading support — treat the new probability with caution.
The pricing has weak support: moderate trading volume, an unusually wide spread. The probability moved another 31 points in the past hour — the market is still repricing.
How credible was the move?
Three separate questions — a move can be genuine while the latest price is still settling. Methodology →
Move validity
Is the move backed by real trading and depth?
WeakThe pricing has weak support: moderate trading volume, an unusually wide spread.
Consensus stability
Has the market settled at the new probability?
UnsettledThe probability moved another 31 points in the past hour — the market is still repricing.
Contract clarity
Will the rules resolve without ambiguity?
HighThe resolution rules are relatively specific, with a named source and a defined deadline.
From the latest trade tape (most recent 200 prints) — a live activity sample, not a lifetime total.
What this market actually measures
This market will resolve to “Yes” if Saudi Arabia takes a qualifying military action against Yemen on the specified date, Yemen Standard Time. Otherwise this market will resolve to “No.” A qualifying military action refers to an air strike or a surface-to-surface missile strike, initiated by Saudi Arabia, that directly impacts Yemen.
This summary shows the opening of the venue's official rules. ProbCast has not yet generated an independent plain-English interpretation for this contract — review the full rules before relying on it.
View full official resolution rules
This market will resolve to “Yes” if Saudi Arabia takes a qualifying military action against Yemen on the specified date, Yemen Standard Time. Otherwise this market will resolve to “No.” A qualifying military action refers to an air strike or a surface-to-surface missile strike, initiated by Saudi Arabia, that directly impacts Yemen. An air strike includes bombs, air-to-surface missiles, and air-launched drones. A surface-to-surface missile strike includes one-way attack drones and surface-to-surface missiles such as cruise or ballistic missiles. The qualifying military action must be carried out by the armed forces of Saudi Arabia. Actions carried out by private military contractors, mercenaries, or proxy forces will not qualify. Where a qualifying action is carried out in the course of a coalition or multinational operation, it will qualify only if the armed forces of Saudi Arabia directly conducted the strike. The following actions do not constitute a qualifying military action: Munitions destroyed or intercepted before impact; Surface-to-air missile strikes; Small-arms fire; Ground incursions; Cyber operations; Naval gunfire and artillery fire; Howitzers, artillery pieces, mortars, and rocket artillery (e.g. MLRS systems); Minor surface-to-surface strikes, including short range loitering munitions, FPV drones, and ATGM strikes; Any threat, authorization, or announcement of force that has not been executed. Any munition that is intercepted or destroyed before impact does not constitute a qualifying military action. Debris, fragments, or any wreckage from intercepted munitions that land on Yemen do not constitute a military action regardless of any damage incurred. “Yemen” refers to the terrestrial territory of Yemen, including its internal waters. Yemen’s maritime territory and airspace are not encompassed. Where territorial borders are disputed, all territory claimed by and under the de facto control of Yemen as of market creation will qualify. The occurrence, attribution, and timing of a qualifying military action will be primarily determined based on a consensus of information available from the resolution sources. Where multiple sources conflict regarding the occurrence, attribution, or timing of a relevant military action, this market will remain open until the earlier of: i) the confirmation of the occurrence, attribution, and timing of the action based on a consensus of information available from the resolution sources or ii) 3 full calendar days (Yemen Standard Time) from the date of the first credibly reported evidence of the action. If this period would extend past the end date, this market will remain open to allow for 3 full calendar days to pass. At the end of the third calendar day, if conflicting reports remain, the incident will be adjudicated based on the totality of information available from the resolution sources at that time. No single statement, denial, or presentation of evidence will govern where it is contradicted by the totality of information. The resolution sources for this market will be official information from the governments and militaries of Saudi Arabia and Yemen, the Houthis, and a consensus of credible reporting.
Why the odds moved
The probability rose 33.0 percentage points over the last 24 hours (48.5% → 81.5%).
No verified catalyst has been linked to this move yet. ProbCast does not attribute moves to news without evidence connecting the timing of a specific report to the repricing.
What could move this market next?
- The latest eligible start date passesSeptember 28, 2026 at 4:59 PM ET
After this date, no new qualifying period can begin under the rules.
- Completion of the qualifying period defined in the rules
Resolution follows once the defined period finishes without a disqualifying event.
Derived from the contract's own mechanics as of Sep 20, 10:35 AM ET. ProbCast does not list scheduled meetings, announcements, or data releases it cannot verify.
Probability by deadline
The same event, priced across deadline contracts on this venue.
- By Sep 28 (this market)81.5%
- By Sep 3031.5%
Extending the deadline from Sep 28 to Sep 30 removes about 50.0 percentage points of implied probability.
Advanced analysis (experimental)
Research signals — these models are still accumulating the history needed for full validation, and they can disagree with the headline read. Model confidence: low · expected error ±34 pts.
What's happening
The price is actively repricing on real volume. The number is still moving — don't treat the latest print as settled consensus yet.
- Probability moved 33.0 pts in ≤6h on adequate liquidity
Read the latest price with caution; conditions make it an unreliable summary right now.
More details — reliability score, dynamics, durability
- Thin-liquidity spike64%
- Choppy / mean-reverting17%
- News repricing8%
Short-term motion of the price line (~1h), distinct from the environment above — not a prediction of the final outcome.
Secondary read: leaning toward Trending.
A read-only classification of the market environment — how much weight the current price deserves as a read of consensus. It describes conditions, never a trade.
Market data
24h volume
$36.2K
Liquidity
$48.4
Total volume
$36.3K
- Category
- Geopolitics
- Venue
- Polymarket
- Open interest
- —
- Spread
- 17.0 pts
- Best bid
- 73.0%
- Best ask
- 90.0%
- 7-day range
- 45.5% – 81.5%
- Resolves
- Sep 28, 2026