🔥 News & Announcements
Polymarket performed a platform-wide bulk rules update on September 25, 2026, adding a standardized erroneous-data clause to hundreds of daily temperature markets across dozens of cities (including Austin, Atlanta, Beijing, Buenos Aires, Busan, Cape Town, Chicago, Chengdu, Chongqing, Dallas, Denver, Guangzhou, Helsinki, Houston, Istanbul, Jeddah, Jinan, Karachi, Kuala Lumpur, London, Los Angeles, Lucknow, Madrid, Manila, Mexico City, Miami, Milan, Moscow, Munich, New York City, Panama City, Paris, Qingdao, San Francisco, São Paulo, Seattle, Seoul/Incheon, Shanghai, Shenzhen, Singapore, Taipei, Tel Aviv, Tokyo, Toronto, Warsaw, Wellington, Wuhan, Zhengzhou, and others) for dates September 25–27, 2026. The added clause states: if the resolution source publishes clearly erroneous data due to technical/operational error or unauthorized interference, the market may remain open up to 7 calendar days (ET) awaiting a correction; if corrected data is published within that window it governs resolution; if not, Polymarket will issue a Clarification to determine next steps. Staff member ak504111 clarified that this clause covers only clearly wrong published values (e.g. an impossible reading), and does not override existing missing-data or revisions clauses.
Hong Kong temperature markets (September 25 & 27, thresholds 21°C–31°C) received an additional, stricter rule: only the Hong Kong Observatory's initial publication counts for resolution — post-publication revisions are ignored — with the erroneous-data exception still applying.
The BAL vs. NYY game originally scheduled for September 26 at 7:15 PM ET has been rescheduled to the 2nd game of a doubleheader on September 25 at 7:05 PM ET. Dozens of associated player prop markets (hits, RBIs, total bases, strikeouts, earned runs, outs, home runs, stolen bases for players including Gunnar Henderson, Pete Alonso, Jazz Chisholm Jr., Cody Bellinger, Trevor Rogers, and others) received bulletin board updates reflecting this change.
Additional MLB schedule clarifications: CHC vs. BOS markets originally listed September 27 were rescheduled to September 25 as the 1st game of a doubleheader (1:05 PM ET); the September 25-listed CHC vs. BOS markets become the 2nd game (5:35 PM ET); BAL vs. NYY markets originally listed September 26 now refer to the 2nd game of the September 25 doubleheader. The BAL vs. NYY September 25 markets (originally the September 26 game) now start at 4:05 PM ET as the 1st game.
Rebate policy update: Polymarket announced removal of crypto rebates applied during their testing period. All rebates will henceforth follow public rebate tiers (onchain and verifiable). Market makers splitting volume across multiple accounts may aggregate volume to maintain tier status by application, provided they can prove the threshold is met.
The AK-AL House seat markets (covering candidates A–E, Democratic, Republican, and another party) received a clarification: candidates listed as options will not be considered to represent any party for resolution purposes, regardless of any subsequent caucus decision.
⚠️ Bugs & Issues
Several technical issues were reported. The incremental order book subscription API is experiencing price_change timestamp delays of 10+ seconds (reported by zero.0674). FAK (Fill and Kill) order times have been exceeding 10 seconds for nearly a week with no resolution. Sequential API GETs for the same order are returning inconsistent statuses (LIVE → CANCELLED → LIVE → LIVE). GTC post-only orders reaching MATCHED status with a sub-minimum remainder (<0.01 shares) are being auto-terminated without a CANCELLATION event; the community workaround is to treat remainders below 0.01 shares as cancelled dust. Order timeout errors are recurring, and the market WebSocket still lacks sequence numbers. The new v2 trades API has CORS restrictions preventing calls from the UI. Historic order book data is not available via API; a third-party archive at
archive.pendulumflow.com was mentioned as an alternative.Other