The probability that the US will announce a blockade on Iran by August 31 surged 20.0 percentage points in the past 24 hours on Polymarket, climbing from an estimated 27.0% to 47.0% as of July 12. This sharp repricing coincided with significant whale activity, which supported the upward move rather than opposing it.
Whales contributed a net $25K in buy flow into YES contracts, with $47K in whale buy volume against $21K in sell volume. A total of 107 unique whales participated in this surge, indicating broad engagement among large traders. The overall 24-hour trading volume on this market reached $55K, a substantial portion of the market’s lifetime volume of $136K. Meanwhile, Polymarket’s on-chain mid-price, tracked by Polydata, lagged behind at 35.5%, highlighting a divergence between the platform’s live prices and the on-chain data snapshot.
The combined data show a strong consensus among large traders backing the increased odds, pushing the market price well beyond prior levels. The alignment of whale flow with the price rise suggests conviction behind this move, reflecting growing expectations of a US blockade announcement within the specified timeframe. This shift substantially alters the market’s risk perception and liquidity profile, marking a notable change in trader sentiment on this geopolitical event.
| Market | Will the US announce a blockade on Iran by August 31? |
|---|---|
| Market ID | 2821347 |
| 24h price change | +20.0 pp |
| YES now (PM Breaking) | 47.0% |
| YES ~24h ago (est.) | 27.0% |
| YES (Polydata overview) | 35.5% |
| Whale net flow (24h) | $25K |
| Whale buy / sell (24h) | $47K / $21K |
| Unique whales (24h) | 107 |
| Volume 24h (PM) | $55K |
| Unique traders (Polydata) | 257 |
Source: Polydata API v3 · /whales/flow + Polymarket Breaking · snapshot 2026-07-12. Data: Polydata API v3. On-chain figures are public. Realized PnL is computed over resolved markets only and excludes open positions, so it is conservative versus the Polymarket UI. This is not investment advice.