Analytics
“SPY Opens Up or Down on August 17?” is a prediction market on Polymarket with two tradeable outcomes, Yes and No. The Yes price is the crowd's implied probability that the question resolves Yes; every trade on the public order book moves it.
The venue reports this market as closed. Its scheduled close is Aug 17, 2026. No resolved outcome is inferred from a closed or suspended state.
Vultax observes this market from Polymarket's public order book and data API and keeps its own record: 3 hourly price points from Aug 17, 2026 to Aug 17, 2026 (Yes between 0.1% and 91.5%); 5 loaded holder wallets, the largest ten holding 100.0% of the loaded shares; 6 recent public fills from 4 wallets. Each figure carries its observation time; nothing here is a return forecast.
Public Polymarket market/event context is available; Vultax source-pack coverage is tracked separately.
This resolved market has no live orderbook depth; the public close quote is shown for context.
Nine stops, one per figure on this page. Each stop says what the number is, why it matters, and what it reads right now for this market.
Each outcome trades as a share that pays $1 if it wins and nothing if it loses. Prices are quoted in cents, and Yes plus No add up to about one dollar.
This market will resolve to "Up" if the open price for S&P 500 (SPY) on August 17, 2026 is higher than the closing price for SPY on the most recent prior trading day. This market will resolve to "Down" if the open price for S&P 500 (SPY) on August 17, 2026 is lower than the closing price for SPY on the most recent prior trading day. E.g., ordinarily, a market on Monday would refer to the previous Friday for its most recent closing price, unless that Friday were a market holiday, in which case it would refer to Thursday, or the next most recent trading day. If the two specified prices are exactly equal, this market will resolve 50-50. Prices will be used exactly as published by Pyth, without rounding. If S&P 500 (SPY) does not trade at all during the regular session, the market will resolve 50-50. The open price refers to the Pyth "Open" value of the 1-minute candle corresponding to the first minute of regular trading hours on the primary exchange. The closing price refers to the Pyth "Close" value of the 1-minute candle corresponding to the final full minute of regular trading hours on the primary exchange (for a standard full session, the candle beginning at 3:59 PM ET; for a shortened session, the candle beginning one minute before the scheduled early close). If either of the relevant days has no valid Pyth Open/Close value for the 1-minute candle corresponding to the beginning/end of regular trading hours on the primary exchange, the market will use the first/last valid Pyth price achieved during the regular trading hours of the primary exchange as the effective price. If no valid Pyth price exists for that trading day due to a system outage, data failure, or other technical disruption, the official open or closing price (as applicable) published by the primary exchange on which the listed security trades will be used to determine the effective price for that day. Only prices achieved during the regular trading hours of the primary exchange on which the listed security trades (typically 9:30 AM – 4:00 PM ET) will be considered. In the event of a stock split, reverse stock split, or similar corporate action affecting the listed security during the listed time frame, this market will resolve based on split-adjusted prices as displayed on Pyth. The resolution source for this market will be Pyth, specifically the "Open" and "Close" values for the relevant 1-minute candle available at https://pythdata.app/explore/Equity.US.SPY%2FUSD. Historical 1-minute candles may be accessed by appending a Unix timestamp (seconds) to the Pyth chart URL using the "t=" parameter. Any timestamp within the listed market time frame may be used to view the relevant candle data (e.g., https://pythdata.app/explore/Equity.US.SPY%2FUSD?t=1773432000).
Official listing: polymarket.com/event/spy-opens-up-or-down-on-august-17-2026
The Yes price read as a chance. A share at 21.5¢ means the crowd gives Yes about a 21.5% chance right now. It moves with every trade, so it is a live forecast, not a verdict.
Dollar value of shares that changed hands in the last 24 hours. High volume means the price is being tested by real money; low volume means a few trades can move it.
Dollars resting in the order book, waiting to be traded against. Deep liquidity lets a large order fill near the quoted price; thin liquidity means the price jumps when someone trades size.
The gap between the best bid and the best ask. A tight spread makes entry and exit cheap; a wide spread is a cost paid on every round trip.
The wallets holding the most shares on each side, and how much of the loaded sample the largest ten control. Concentration shows whether a market is a crowd or a handful of large positions.
The public fills, newest first: which wallet bought or sold which outcome, at what price, and when. It is the market's own diary, and every wallet on it links to a trader profile.
Hourly closes of the Yes price. The range shows how sure or split the crowd has been; the move shows which way it has been changing its mind.
Trading stops at the close time. The outcome is then settled by the resolution source named in the rules. A closed market is not resolved until the venue reports it, so the two states are shown separately.
| Up |
| 89.47 |
| pablosanchez | Up | 20 |
| TENETENET | Up | 10 |
| bjprolo | Up | 5 |
| triklozoid | Up | 5 |