The Pre-Open Auction: Why 9:00 to 9:15 AM Prices Lie

Abstract

Between 9:00 and 9:15 AM the screen shows prices that no one has traded at. The index figure is indicative while orders are collected, and option prices are the previous session's close until the first trade at 9:15 AM. Version 2 (October 8, 2026): the pre-open timings were corrected to the schedule in force since September 7, 2026, and sources were added. Version 1 gave the earlier schedule. AION Analytics research note. Canonical version: https://aionanalytics.in/research/notes/pre-open-auction