a16z and the DeFi Education Fund asked the Securities and Exchange Commission on September 14 to create a safe harbor treating decentralized exchange protocols and their front-ends as outside the legal definition of an "exchange" under the Exchange Act, according to a joint proposal submitted to Commissioner Hester Peirce.

The filing asks the agency to establish a rebuttable presumption that non-custodial trading protocols and their user interfaces do not meet the statutory criteria of an exchange. That mechanism would invert the current posture under which DEX developers must argue on a case-by-case basis that their software does not constitute a regulated venue.

What would the safe harbor cover?

The proposal targets two distinct layers: the underlying smart-contract protocol and the front-end application users interact with. Both would receive the same presumption against exchange status. The groups argue that front-ends operated by independent parties should not inherit obligations triggered by the protocol itself.

Peirce, who has overseen much of the Commission's recent crypto policy work, is the named recipient. The proposal lands three days before the agency issued an "Innovation Exemption" tailored to tokenized stock venues on September 17, a move that confirms market-structure questions around DeFi remain a live agenda item for the Commission.

What is a16z asking for centralized venues?

The venture firm filed a second letter the same day, pressing the SEC to construct a registration framework for centralized crypto trading platforms modeled on the 1998 alternative trading system, or ATS, rules. That regime governs broker-dealer-operated electronic marketplaces and offers a lighter disclosure and operational path than full national-exchange registration.

The parallel structure of the two filings is deliberate. By separating non-custodial protocols from custodial platforms, a16z is mapping a two-track regulatory architecture: presumption-of-exemption on one side, modified registration on the other.

What changes if the SEC adopts the proposal?

A safe harbor with a rebuttable presumption would shift the litigation burden onto the agency or private plaintiffs who claim a particular DEX falls within the Exchange Act. For protocol developers and front-end operators, the practical effect is lower enforcement risk absent specific findings of centralized control or fraud.

The proposal stops short of mandating a definitional rulemaking. Instead, it relies on the Commission to formalize the presumption through exemptive relief, interpretive guidance, or a targeted rule.

How does this connect to the broader rulebook?

The September 17 Innovation Exemption is the SEC's first formal accommodation of tokenized-equities trading. Read together with the a16z and DeFi Education Fund letters, the three documents sketch a market-structure perimeter that distinguishes among self-custodial DeFi trading, centralized crypto platforms, and tokenized securities. Each category would receive a different treatment, ranging from safe-harbor protection to a tailored registration regime to an existing exemptive order.

The Commission's next move is uncertain. Peirce's public posture and the timing of the filings suggest the agency is consulting industry before finalizing its approach. Formal rulemaking on exchange definition, if pursued, would likely proceed through a notice-and-comment process measured in months rather than weeks.