When writing this article, I missed a @ Backpack_CN. In fact, BackPack also has its own brokerage service entity, Backpack Securities Global Ltd, as a global operating entity, following the legal framework of New York State and with DTCC as the settlement layer. So in reality, both Coinbase Binance BIT and Backpack have a three-tier structure, consisting of an exchange front-end, proprietary service brokers, and underlying settlement brokers. So I think a more accurate classification would be as follows: Coinbase is a domestic broker dealer route in the United States, serving American users and starting with traditional US stocks and ETFs. The structure of Binance is the front-end of Binance, with Nest Trading serving as the introducing broker, and then routing securities orders to Alpaca, which is responsible for execution, clearing, settlement, and custody. Preview bStocks later. The structure of BIT is also similar, with its own front-end and underlying stock trading being partnered with American licensed securities firms, and has established partnerships with three American licensed institutions: Clear Street, RQD Clearing, and Atomic Vaults Securities (AVS). Backpack is the front-end of Backpack, where Backpack Securities serves as the main securities service provider and completes securities holding, transfer, and settlement through traditional brokerage infrastructure, ACATS, and DTCC compatible systems. At the same time, it connects traditional securities with tokenized securities on the chain. So the commonality among these four platforms is that they have not directly turned the exchange into a securities clearing and custody institution, but have added a layer of their own securities service providers between the exchange and the underlying US stock infrastructure. This intermediate layer is crucial. Because it addresses the issue of how cryptocurrency exchanges can integrate with traditional securities. The difference is that Coinbase can serve American users, while the other three cannot serve American users.