24X would generally bar clearly erroneous review of overnight trades inside 20% bands

24X National Exchange LLC has filed to align its clearly erroneous executions rule with the overnight LULD bands approved in August. In a notice dated 10 Nov (Release No. 34-106867, SR-24X-2026-31), filed on 3 Nov, 24X said it would amend Rule 11.14 “in light of the Commission’s approval of Overnight Protected Bands under the LULD Plan for 23/5 Trading.”

The Commission approved the 27th amendment to the LULD Plan on 5 Aug (Release No. 34-106042, File No. 4-631), as Midpoint has reported. 24X recites that the LULD Plan Operating Committee proposed Overnight Price Bands that “would initially be temporary static bands 20% above and below two reference points.” In the same filing, 24X defines “Overnight Price Bands” as those “that apply to the Overnight Protected Hours from 9:00 p.m. ET through 4:00 a.m. ET.” “LULD Protected Hours” would include Regular Trading Hours and those Overnight Protected Hours.

What would change in Rule 11.14

24X’s current rule, the filing says, has as its “central premise” that “if LULD Price Bands under the LULD Plan were available and correct at the time the transaction was executed, the transaction is not eligible for clearly erroneous review.” That restriction now applies only during Regular Trading Hours, “meaning that the restrictions on clearly erroneous review described above apply only during Regular Trading Hours.”

24X now proposes “to extend the existing restrictions on clearly erroneous review to the period when Overnight Price Bands are in place.” It would amend the first sentence of Rule 11.14(c)(1) to replace the phrase “Regular Trading Hours” with “LULD Protected Hours,” to provide that “[i]f the execution time of the transaction(s) under review is during LULD Protected Hours, the transaction will not be reviewable as clearly erroneous … .” The filing lists limited circumstances already in the rule, including when the transaction is in an NMS stock “that is not subject to the LULD Plan (e.g., rights and warrants),” or was “executed at a time when LULD Price Bands were unavailable or trading should have been prevented due to a regulatory halt or other halt.”

In its statutory basis, 24X said “clearly erroneous review should be generally unavailable any time a transaction is executed within LULD Price Bands at a time the Price Bands were available and correct.” The change, it said, “would limit any potential discordance between the LULD mechanism and CEE review in the overnight trading session, providing greater certainty to market participants that trades executed with the Overnight Price Bands will stand and not be broken.”

Transactions in NMS stocks not subject to the LULD Plan that are executed during the Overnight Protected Hours “would be subject to the same Numerical Guidelines as transactions occurring in the Pre-Market Session and Post-Market Session.”

Currently, “transactions executed during the 24X Market Session are treated in the same manner as transactions executed during the Pre-Market and Post-Market Sessions.” 24X proposes instead “to make clearly erroneous review of transactions executed during the 24X Market Session available in a manner similar to transactions executed during Regular Trading Hours.”

Timing and other venues

The filing became effective on filing under Section 19(b)(3)(A)(iii) and Rule 19b-4(f)(6). Unless the Commission designates a shorter period, it does not become operative until 30 days after the 3 Nov filing date. “The Exchange proposes that this rule change would become operative at the commencement of 23/5 Trading, which is scheduled to commence industry-wide on December 6, 2026.”

“The Exchange understands that the other national securities exchanges and FINRA will also file similar proposals, the substance of which are identical to this proposal.” That is 24X’s understanding. The filing does not name those other exchanges or attach their proposals, and this article does not treat an industry-wide change as already on file.

Why it matters

Analysis. The August order put 20% overnight bands on the LULD Plan. This filing is about what happens to a print that lands inside those bands on 24X. Under the proposal, from the 6 Dec 23/5 start, such a trade would generally not be reviewable as clearly erroneous, matching the regular-hours premise. Overnight desks that have treated the 24X Market Session more like pre- and post-market, where clearly erroneous review is still available, would need to adjust that expectation for the Overnight Protected Hours window of 9:00pm to 4:00am ET.

The rule is not an absolute bar. Stocks outside the LULD Plan, and trades when the bands were unavailable or when a regulatory halt or other halt should have prevented trading, would still be eligible for review. For rights and warrants overnight, 24X would apply the same numerical guidelines it uses in the pre-market and post-market sessions.

Whether the same standard applies across the rest of the 23/5 complex depends on filings that 24X only says it understands will be made. Those should be read as they appear, venue by venue.

What we are watching

• Whether other national securities exchanges and FINRA file the similar proposals 24X says it understands are coming, and whether they also become operative on 6 Dec.
• How 24X treats the limited exceptions, including trades when Overnight Price Bands were unavailable.

Sources

• Release No. 34-106867 (SR-24X-2026-31): Notice of Filing and Immediate Effectiveness of Proposed Rule Change to Amend Rule 11.14, U.S. Securities and Exchange Commission, notice dated 10 Nov 2026
• Release No. 34-106042 (File No. 4-631): Order Granting Approval of the Twenty-Seventh Amendment to the LULD Plan, U.S. Securities and Exchange Commission, dated 5 Aug 2026, published in the Federal Register on 10 Aug 2026