Nasdaq amends Rule 4759 to use CQS/UQDF for Night Session data
The change applies to Nasdaq's Night Session trading, effective immediately on August 17, 2026.
On August 17, 2026, The Nasdaq Stock Market LLC filed a proposed rule change with the SEC, identified as Release No. 34-106169; File No. SR-NASDAQ-2026-067. The notice, published in the Federal Register on August 25, 2026 (Vol. 91, No. 163, FR Doc No: 2026-17279), states that the amendment is effective immediately.
The amendment revises Equity 4, Rule 4759(a) to specify that, during the Night Session - defined as the period from 9:00 p.m. to 4:00 a.m. ET Sunday through Thursday, subject to Equity 1, Section 1(a)(19) - Nasdaq will use CQS/UQDF as the sole source of quotation data for order handling, routing, execution, and related regulatory compliance functions.
Nasdaq explains that the Night Session presents distinct operational considerations. Using CQS/UQDF allows the Exchange to make the required timestamp adjustments for extended-hours trading without altering the proprietary feed handlers that serve the Day Session. The change does not modify the list of primary and secondary market-center feeds in Rule 4759(a) nor the Exchange's use of SIP trade and administrative data under Rule 4759(b).
The full text of the proposed rule change is available on Nasdaq's website at https://listingcenter.nasdaq.com/rulebook/nasdaq/rulefilings and at the Exchange's principal office. Comments are solicited pursuant to Section 19(b)(1) of the Securities Exchange Act of 1934 and Rule 19b-4.
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