SEC Proposes Historic Overhaul: The End of Regulation NMS Rules 611 and 610(e)

WASHINGTON, D.C. — June 11, 2026 — In a move that signals the most significant shift in U.S. equity market structure in two decades, the Securities and Exchange Commission (SEC) announced today that it has formally proposed amendments to rescind Rules 611 and 610(e) of Regulation National Market System (Reg NMS). This proposal represents a pivot away from the centralized, mandate-heavy regulatory framework that has governed American stock exchanges since 2005, ushering in a new era of decentralized competition.

Main Facts: The Proposed Deregulation

The SEC’s proposal, released Wednesday, targets the "Order Protection Rule" (Rule 611) and the "Access Fee Cap" (Rule 610(e)). Under the existing Reg NMS framework, Rule 611 requires trading centers to establish, maintain, and enforce written policies reasonably designed to prevent "trade-throughs"—the execution of trades at prices inferior to those displayed by another trading center. Essentially, it forces market participants to route orders to the exchange showing the best publicly quoted price.

Rule 610(e), meanwhile, currently limits the fees that exchanges can charge for accessing their "protected" quotes. By proposing the rescission of these rules, the Commission is effectively signaling that it believes the technological landscape of 2026 has outgrown the rigid protections established in the mid-2000s.

SEC Chairman Paul S. Atkins, in a prepared statement, emphasized that the regulatory environment of the early 21st century has inadvertently created a "cluttered, fragmented, and overly complex" ecosystem. "After two decades of Rule 611, it is high time that the Commission review its unintended consequences that have hindered—rather than enhanced—the long-term growth of our markets," Atkins stated.

A Chronology of Regulation NMS

To understand the gravity of today’s announcement, one must look back at the genesis of the current system.

• 2005: The SEC adopts Regulation NMS, aimed at modernizing the national market system. Its primary goal was to ensure that investors received the best price regardless of which exchange they used, curbing the problem of "trade-throughs" in an increasingly electronic environment.
• 2007: Reg NMS becomes fully operational. The industry undergoes a massive technological upgrade to meet the compliance requirements of Rule 611, leading to the rise of high-frequency trading (HFT) firms that specialize in latency arbitrage.
• 2010–2015: As the market becomes dominated by dark pools and fragmented electronic communication networks (ECNs), critics begin to argue that Rule 611 has created a "siloed" market where liquidity is trapped, rather than truly consolidated.
• 2020–2024: The rise of retail-focused trading apps and the move toward T+1 settlement cycles place unprecedented stress on the legacy infrastructure of Reg NMS. Market participants call for modernization.
• 2026: The Commission initiates the formal process to rescind the two pillars of the regulation, seeking to return pricing discovery to the competitive forces of the market rather than federal mandate.

Supporting Data: The Case for Change

The SEC’s proposing release provides extensive data on why the current rules are no longer fit for purpose. While the original intent of Rule 611 was to protect retail investors, the Commission’s analysis suggests that the cost of compliance—specifically the "latency tax" imposed by the need to check all exchanges before executing a trade—has grown exponentially.

The Complexity Burden

Internal SEC studies cited in the proposal note that the number of "protected" quotes has grown by over 400% since 2005, yet the quality of execution has not seen a commensurate improvement for retail investors. Instead, the complexity has fueled a "latency race" where firms spend billions on microwave towers and fiber-optic optimization simply to comply with the technical requirements of the Trade-Through Rule.

Market Fragmentation

Critics of the existing system have long argued that Reg NMS created "liquidity fragmentation." By forcing trades to be broken up to satisfy price requirements across dozens of venues, the system often increases the total cost of execution through fragmented fill rates and higher market impact. The data suggests that rescinding these rules could consolidate liquidity back into larger, more transparent venues, as exchanges would have to compete on the quality of their service rather than merely being the "best price" repository.

Official Responses and Stakeholder Sentiment

The announcement has sparked a firestorm of debate across Wall Street, Washington, and academia.

The SEC’s Perspective

Chairman Atkins remains steadfast in his belief that the market has matured to a point where it can govern itself. "This proposal is intended to simplify market structure and reduce costs for market participants while allowing competition, innovation, and other market forces to shape the continuing evolution of our equity markets," Atkins said. He noted that the Commission is adopting a "careful, deliberative approach" to ensure that the transition does not result in market instability.

Industry Reactions

• Exchange Operators: Major exchanges have reacted with a mix of caution and optimism. While some fear that the loss of the "protected" status of their quotes could reduce their market share, others argue that removing fee caps (Rule 610(e)) will allow for more sustainable revenue models that support deeper market liquidity.
• Institutional Investors: Pension funds and asset managers have expressed concerns regarding "best execution." There is a lingering fear that without the protection of Rule 611, institutional orders could be executed at inferior prices in "dark" or off-exchange venues, potentially harming long-term retirement savers.
• The Fintech Community: Disruptive fintech firms have largely cheered the move. Many argue that Reg NMS acted as a moat for incumbents, making it difficult for new, agile trading venues to compete with established exchanges.

Implications: The Future of Equity Markets

The rescission of Rules 611 and 610(e) carries profound implications for the future of U.S. finance.

1. The Death of the Latency Race?

If the requirement to route orders based on the "best protected quote" is removed, the advantage of being a millisecond faster than a competitor may diminish significantly. This could lead to a massive reallocation of capital away from high-frequency infrastructure and toward research, technology, and human capital.

2. A Shift in Liquidity

Markets may see a return to "centralized" trading. Without the incentive to fragment orders to meet the requirements of multiple venues, trading activity may consolidate into a few dominant exchanges, effectively reversing two decades of market fragmentation. Alternatively, it could lead to the proliferation of niche venues that offer specialized services, as the regulatory "one-size-fits-all" requirement vanishes.

3. The Return of Negotiated Fees

The removal of the fee cap under Rule 610(e) will fundamentally change the economics of trading. Exchanges will be free to set their own access fees, which will likely lead to a new era of price competition. This could result in lower costs for some investors and higher costs for others, depending on the venue they choose.

4. Regulatory Oversight in a Post-NMS World

The SEC’s role will shift from "rule-maker" to "referee." The Commission will likely increase its focus on anti-fraud and transparency enforcement to ensure that, in the absence of Reg NMS, broker-dealers continue to fulfill their fiduciary duty of "best execution" to their clients.

The Path Forward: Public Comment

The SEC has opened a 60-day window for public comment, inviting stakeholders from across the spectrum to weigh in on the proposal. This period is expected to be one of the most contentious in recent memory, as industry players prepare for the possibility of a total rewrite of the rulebook.

"I look forward to reviewing public comments as we take a careful, deliberative approach to avoid repeating the same mistakes that brought us here," Chairman Atkins concluded.

As the industry digests the 400-page proposal, one thing is certain: the era of Reg NMS is coming to a close. Whether this leads to a more efficient, competitive, and robust market or a period of volatility and uncertainty remains the central question facing the U.S. financial system in the coming year. For now, market participants are bracing for a period of transition that will redefine how stocks are traded, priced, and valued in the world’s most important capital market.