The Securities and Exchange Commission convened a Roundtable on Preparations for 24-Hour Trading featuring three panels and 27 participants, and dedicated one of those panels to operational resiliency, Jim Toes, president and CEO of the Securities Traders Association, wrote this week. The agenda catalogued the systems work that U.S. equity trading demands as the session extends from a 9:30 a.m. to 4:00 p.m. ET window toward 23 hours per day, five days per week.

What did the resiliency panel cover?

The session mapped the operational tasks facing exchanges, alternative trading systems, market makers and broker-dealers in a near-continuous market. Panelists worked through six problem sets:

• Systems readiness under Regulation SCI
• Failover design and capacity planning
• Market-data continuity across the expanded window
• Compressed maintenance windows
• Cybersecurity controls and overnight threat monitoring
• Staffing models that cover the new pre-market and post-close hours

Who sat on the panel?

The commission drew participants from competing venues and competing broker-dealers. Toes flagged the deliberate mix: exchanges that route against each other, ATSs that take liquidity from one another, market makers that price the same names, and broker-dealers that route among them. Each firm described its own architecture, its own risk-management culture and its own points of failure.

Why does that mix matter for resiliency?

A localized outage does not propagate across the market when several competitors remain open and able to absorb flow, Toes wrote. Redundancy emerges from rivalry rather than from any single regulator. Where one operator's switch fails, another operator's healthy session can continue to print trades, publish quotes and clear positions.

The rivals at the table were not identical copies of one another. They run different matching engines, different clearing paths and different data distribution systems. A failure that originates in one stack does not automatically migrate through the others, Toes argued.

What does competition add beyond regulation?

Toes drew a line between the Commission's investor-protection mandate and the role of rivalry in setting operational standards. Regulation SCI establishes a baseline. Competitive pressure sits above that baseline and compels firms to spend on capacity they would not otherwise maintain.

"Fostering competition can never be overstated for its contribution to resiliency," Toes wrote. "Resiliency is not only a regulatory outcome. It is also a competitive one."

He continued: "Competitive markets force participants to innovate around single points of failure, to maintain spare capacity, and to treat operational excellence as a product feature rather than a compliance requirement."

The phrase compresses the argument into one mechanism. Firms that market uptime and data integrity to clients capture order flow. Firms that treat resiliency as a checkbox do not.

What is the regulatory timeline?

The roundtable produced no rule, no proposal date and no compliance deadline. U.S. equities have already begun the move toward a 23-by-5 window, and the commission has signaled that a fully continuous session remains under consideration. Toes tied the speed of the transition to the operational posture of the firms involved.

What should execution desks track next?

Two data points will shape how the rollout changes workflow. First, the Commission's next proposal on overnight session rules, including any limits on order types, cancellation rights and price-discovery mechanisms during the extended hours. Second, the failover capacity and published SCI disclosures from competing venues, since the resiliency argument rests on whether alternative operators can absorb flow during an outage at a primary exchange.

Desks that build their contingency routing around those two disclosures will know which venues still print when one fails, and Toes's core prediction is straightforward: firms that compete on uptime, data integrity and risk controls will attract the capital that 24-hour trading is expected to draw.