IEX proposes amendment to Rule 11.271 to retain 4 a.m. resume after Level 3 halt

Pursuant to Section 19(b)(1) of the Securities Exchange Act of 1934 and Rule 19b-4, Investors Exchange LLC filed a proposed rule change on November 2, 2026 (Release No. 34-106810; File No. SR-IEX-2026-45). The notice, published in the Federal Register on November 9, 2026 (FR Doc No. 2026-22752), solicits comments and states that the change is effective immediately.

The proposal seeks to amend Rule 11.271(b)(2), which currently requires that a Level 3 market-wide circuit breaker halt "for the remainder of the trading day" suspend trading. IEX proposes to delete that language and replace it with explicit wording that trading in all stocks will halt "until 4:00 a.m. Eastern Time or later on the following trading day."

The amendment is motivated by the upcoming expansion of trading by other national securities exchanges to 23 hours per day, five days per week, scheduled to begin on December 6, 2026. Under the existing rule, the phrase "remainder of the trading day" would trigger a resumption as early as 9:00 p.m. Eastern Time on the same calendar day for exchanges operating overnight sessions. IEX argues that such an earlier resumption is neither expected nor desired and would diverge from current market practice.

IEX characterizes the filing as non-controversial and notes that the change is coordinated with other self-regulatory organizations to preserve the uniform 4:00 a.m. Eastern Time resumption time across all exchanges following a Level 3 halt. The amendment does not alter the substantive mechanics of the market-wide circuit breaker, only the timing of trading reinstatement.