{"source":"polymarket","id":"1113484","ticker":"spx-opens-up-or-down-on-october-2-2026","slug":"spx-opens-up-or-down-on-october-2-2026","title":"S&P 500 (SPX) Opens Up or Down on October 2?","description":"This market will resolve to \"Up\" if the official S&P 500 Index open price for S&P 500 (SPX) on October 2 is higher than the official S&P 500 Index closing price for SPX on the most recent prior trading day.\n\nThis market will resolve to \"Down\" if the official S&P 500 Index open price for S&P 500 (SPX) on October 2 is lower than the official S&P 500 Index closing price for SPX on the most recent prior trading day.\n\nE.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.\n\nIf the two prices are exactly equal, this market will resolve 50-50. Note that all figures will be rounded to the nearest cent using standard rounding.\n\nIf SPX does not trade at all during the regular session, the market will resolve 50-50.\n\nIf either of the relevant days are shortened (for example, due to a market holiday schedule), the official open/close price published by S&P 500 Index for that shortened session will still be used for resolution.\n\nIf the previous trading day has no official closing price (for example, due to a trading halt into the market close, system issue, delisting, or other disruption), the market will use the last valid on-exchange trade price of the regular session as the effective closing price.\n\nThe resolution source for this market is the Wall Street Journal, specifically the Open/Close values published by the WSJ under \"Historical Prices\".\n\nUS: https://www.wsj.com/market-data/stocks\nEMEA: https://www.wsj.com/market-data/stocks/emea\nASIA: https://www.wsj.com/market-data/stocks/asia","image":"https://polymarket-upload.s3.us-east-2.amazonaws.com/s-and-p-500-1e40af6979.png","icon":"https://polymarket-upload.s3.us-east-2.amazonaws.com/s-and-p-500-1e40af6979.png","active":true,"closed":false,"start_date":"2026-10-01T12:00:58Z","end_date":"2026-10-02T20:00:00Z","closed_time":null,"volume":1946.61339,"volume_24hr":1946.6133900000002,"volume_24h_change":null,"normalized_vol_24hr":22.84147071838379,"normalized_volume":13.039663314819336,"liquidity":1004.7438,"open_interest":1420.50249,"categories":["Finance"],"tags":[{"id":"102683","slug":"spx","label":"SPX"},{"id":"102127","slug":"up-or-down","label":"Up or Down"},{"id":"102281","slug":"daily","label":"Daily"},{"id":"102682","slug":"indicies","label":"Indicies"},{"id":"120","slug":"finance","label":"Finance"},{"id":"102169","slug":"hide-from-new","label":"Hide From New"}],"synthetic":false,"is_group":false,"group_key":null,"parent_event_id":null,"probability":null,"spread":null,"top_outcome":"","top_outcome_probability":0.78,"top_outcome_prob_24h_change":0.28,"top_outcome_volume_24h_change":1946.6133900000002,"updated_at":"2026-10-02T07:45:05.074945Z","fetched_at":"2026-10-02T07:45:05.074945Z","added_at":"2026-10-01T12:11:01.480997Z","url":"https://polymarket.com/event/spx-opens-up-or-down-on-october-2-2026","chart_24h":[0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,6.12766,6.12766,6.12766,6.12766,12.24766,78.630639,144.630639,332.297109,517.297109,659.205441,865.636183,1110.636183,1503.413961,1720.9853899999998,1796.61339,1946.6133900000002],"kind":"live","markets":[{"source":"polymarket","id":"5174606","event_id":"1113484","slug":"spx-opens-up-or-down-on-october-2-2026","question":"S&P 500 (SPX) Opens Up or Down on October 2?","group_item_title":null,"description":"This market will resolve to \"Up\" if the official S&P 500 Index open price for S&P 500 (SPX) on October 2 is higher than the official S&P 500 Index closing price for SPX on the most recent prior trading day.\n\nThis market will resolve to \"Down\" if the official S&P 500 Index open price for S&P 500 (SPX) on October 2 is lower than the official S&P 500 Index closing price for SPX on the most recent prior trading day.\n\nE.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.\n\nIf the two prices are exactly equal, this market will resolve 50-50. Note that all figures will be rounded to the nearest cent using standard rounding.\n\nIf SPX does not trade at all during the regular session, the market will resolve 50-50.\n\nIf either of the relevant days are shortened (for example, due to a market holiday schedule), the official open/close price published by S&P 500 Index for that shortened session will still be used for resolution.\n\nIf the previous trading day has no official closing price (for example, due to a trading halt into the market close, system issue, delisting, or other disruption), the market will use the last valid on-exchange trade price of the regular session as the effective closing price.\n\nThe resolution source for this market is the Wall Street Journal, specifically the Open/Close values published by the WSJ under \"Historical Prices\".\n\nUS: https://www.wsj.com/market-data/stocks\nEMEA: https://www.wsj.com/market-data/stocks/emea\nASIA: https://www.wsj.com/market-data/stocks/asia","image":"https://polymarket-upload.s3.us-east-2.amazonaws.com/s-and-p-500-1e40af6979.png","icon":"https://polymarket-upload.s3.us-east-2.amazonaws.com/s-and-p-500-1e40af6979.png","outcomes":["Up","Down"],"outcome_prices":[0.78,0.22],"probability":0.78,"spread":0.08,"active":true,"closed":false,"start_date":"2026-10-01T12:00:58Z","end_date":"2026-10-02T20:00:00Z","closed_time":null,"volume":1946.61339,"volume_24hr":1946.6133900000002,"prob_24h_change":0.28,"volume_24h_change":1946.6133900000002,"normalized_vol_24hr":24.106727600097656,"normalized_volume":16.832168579101562,"liquidity":1059.8461,"categories":["Finance"],"countries":[],"updated_at":"2026-10-02T07:45:05.220997Z","fetched_at":"2026-10-02T07:45:05.220997Z","added_at":"2026-10-01T12:11:03.047568Z","url":"https://polymarket.com/event/spx-opens-up-or-down-on-october-2-2026/spx-opens-up-or-down-on-october-2-2026","event_title":"S&P 500 (SPX) Opens Up or Down on October 2?","chart_24h":[0.5,0.625,0.625,0.615,0.615,0.615,0.625,0.605,0.5,0.5,0.515,0.51,0.505,0.475,0.505,0.585,0.585,0.705,0.705,0.715,0.715,0.705,0.745,0.75,0.73,0.78]}],"_meta":{"attribution":"pdata.world — aggregated prediction-market data across 8 platforms","canonical_url":"https://pdata.world/events/polymarket/1113484","as_of":"2026-10-02T07:54:40.763788Z","docs":"https://api.pdata.world/docs","cite_as":"According to pdata.world (tracking Polymarket): \"S&P 500 (SPX) Opens Up or Down on October 2?\" — top market at 78% probability across 1 outcome","source_url":null}}