Market Metrics That Matter: Your Monthly U.S. Cash Equities Volume Briefing

October 6, 2025

September Highlights

Chris Isaacson, Executive Vice President, Chief Operating Officer, participated in the SEC Regulation NMS roundtable advocating for retaining Rule 611 but with targeted modifications. Cboe believes that Rule 611 of Regulation NMS is worthy of review. As always, though, Cboe notes that changes to any one rule can have cascading impacts on other requirements and on the incentives that ultimately shape the marketplace. In this regard, it is important that we consider these implications when considering any significant change to Rule 611. Read Cboe’s letter to the SEC here.
Cboe BYX® Equities Exchange (BYX) Periodic Auctions had over 1,562 unique stocks entered this month. Learn more about Periodic Auctions here.
September notional traded value was $81.1 million with 1,231 distinct stocks trading.
Cboe announced support for transaction fees for U.S. equities as part of the ongoing process of adapting to new SEC rules. Learn more.

Upcoming Changes

November 7, 2025 | Cboe BZX® Equities Exchange (BZX) will update Limit-On-Close (LOC) and Late-Limit-on-Close (LLOC) order behavior to improve Closing Auction stability and enhance price discovery.