The Securities and Exchange Commission has proposed eliminating Rule 611 of Regulation NMS — the Order Protection Rule commonly known as the Trade-Through Rule — citing the reduction of market complexity as its stated objective, according to a TradingView report.

Reg NMS, adopted by the SEC in 2005, governs order handling and execution across U.S. equity trading centers. Rule 611 has required automated trading centers to establish, maintain and enforce written policies preventing trade-throughs: executions at prices inferior to protected quotations displayed by other automated venues.

What does the proposed change target?

Rule 611 sits at the center of routing logic for both sell-side smart order routers and buy-side execution algorithms. Protected quotations consist of the best bid or offer displayed by any automated trading center that immediately and automatically executes incoming orders against that quote.

Under the existing framework, marketable orders must generally be routed to — or the trading center must have policies preventing execution away from — the venue displaying the best protected quote. The rule set has shaped routing-engine design, latency budgets and venue-connection priorities at desks on both sides of the market.

How does Rule 611 shape execution workflow today?

The rule effectively created the protected-quote pecking order that smart order routers have used for two decades. Practically, that means:

• A marketable buy order must access the lowest protected offer before executing anywhere else.
• Off-exchange wholesalers and ATSs face execution duties when their quotes fall outside protected prices.
• Routing engines must monitor protected quotes from all automated centers in real time.

Trading desks have built execution algorithms, TCA models and best-execution frameworks around this protection hierarchy. The order-routing stack — including SOR code paths, market-data infrastructure and post-trade analytics — depends on the protected-quote construct remaining intact.

What changes for buy-side and sell-side desks if Rule 611 goes?

The proposed repeal, as described by the TradingView report, would remove the obligation to prevent trade-throughs of protected quotes. Execution desks could route orders with greater discretion over venue selection, fee structure and latency trade-offs.

That added discretion creates fresh documentation pressure. Best-execution duties under Reg NMS Rule 605, Rule 606 disclosure requirements and the broker-dealer fiduciary obligation to customers would all persist. Firms would need to recalibrate TCA benchmarks, smart-order-router logic and venue-ranking criteria in any post-repeal world.

Market-data consumption costs could also shift if protected-quote surveillance obligations loosen, though specific fee or connectivity changes remain unannounced in the available reporting.

What is mandated versus proposed?

The source identifies the change as a proposal, not a final rule. No SEC release date for the rulemaking, no effective date and no compliance window appear in the TradingView item reviewed.

The Commission must follow the Administrative Procedure Act notice-and-comment process before any repeal becomes binding. Public comment periods for Reg NMS-adjacent changes have historically spanned 30 to 60 days, although no timeline is stated for this specific file.

What to watch next

The next milestones will be publication of the SEC's proposing release with full rule text, the opening of the comment period, and any commissioner statements accompanying the vote. Buy-side and sell-side desks should begin assessing SOR configurability, TCA recalibration paths and documentation frameworks now — well before any eventual compliance deadline arrives.