Andreessen Horowitz, known as a16z, and the DeFi Education Fund asked SEC Commissioner Hester Peirce to establish a safe harbor creating a rebuttable presumption that qualifying decentralized exchange protocols and their front-end interfaces are not exchanges under the Securities Exchange Act of 1934. The letters were dated Sept. 14. In a separate letter submitted the same day, a16z urged the SEC to create an Alternative Trading System-style registration framework for centralized crypto trading platforms. The DEX proposal targets non-custodial, automated, permissionless and credibly neutral protocols, while the centralized-platform framework would provide a compliance pathway for crypto intermediaries. Three days later, the SEC issued an Innovation Exemption for certain permissioned tokenized securities venues. The SEC has not adopted the proposed DEX safe harbor.