NOTICE DATE: October 13, 2025

NOTICE TYPE: M-C101325-01 Operations

SHORT DESCRIPTION: Price Correction due to SCED Failure

INTENDED AUDIENCE: All Market Participants

DAYS AFFECTED: October 7, 2025

LONG DESCRIPTION: On Operating Day (OD) October 7, 2025, a software defect caused Security- Constrained Economic Dispatch (SCED) to fail to run for intervals 00:00 through 00:25. SCED subsequently ran successfully at 00:28. The root cause was determined to be a SCED software defect that was triggered during the creation of the capped and bounded Energy Offer Curve (EOC) of a Resource.

Upon completion of the impact analysis, ERCOT determined that the impact to prices met the significance criteria in ERCOT Protocols Section 6.3(5) for pursuing a price correction for OD October 7, 2025. ERCOT corrected prices for OD October 7, 2025 before the deadline of October 9, 2025 at 4:00 PM.  Pursuant to ERCOT Protocols Section 6.5.9.2(2), in the process for correcting prices, prices were held for 15 minutes after the 00:28 SCED run.

Price correction files for OD October 7, 2025 have been posted on the Market Information System (MIS).

CONTACT: If you have any questions, please contact your ERCOT Account Manager. You may also call the general ERCOT Client Services phone number at (512) 248-3900 or contact ERCOT Client Services via email at ClientServices@ercot.com.

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