Story perspectives

Chicago Mercantile Exchange Trading Halted Amid Cooling Failure

11/30/2025

Summary

Story summary

On November 28, 2025, the Chicago Mercantile Exchange (CME) halted trading after a cooling failure at CyrusOne CHI1.
The outage began late on November 27, 2025 and froze trading for about ten hours.
Markets were affected globally, with impact in Asia and Europe, as traders could not adjust positions during month-end.
By early afternoon, CME began partial restorations, raising concerns about centralized data infrastructure as many markets remained halted.

History

Historical Context

The 1987 stock market crash, known as Black Monday, saw the Dow Jones Industrial Average drop by 22.6% in a single day, resulting in global losses of approximately $1.71 trillion. This event prompted regulatory reforms, including the introduction of trading curbs. The recent CME outage echoes these historical vulnerabilities, underscoring the ongoing need for robust contingency plans in financial markets.

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Story summary

On November 28, 2025, the Chicago Mercantile Exchange (CME) halted trading after a cooling failure at CyrusOne CHI1.
The outage began late on November 27, 2025 and froze trading for about ten hours.
Markets were affected globally, with impact in Asia and Europe, as traders could not adjust positions during month-end.
By early afternoon, CME began partial restorations, raising concerns about centralized data infrastructure as many markets remained halted.

1 / 2