Stock is centralized, but not in that way. There is no single ordering of transactions. Exchanges (which are distinct entities, i.e. decentralized) are legally

Stock is centralized, but not in that way. There is no single ordering of transactions. Exchanges (which are distinct entities, i.e. decentralized) are legally required to report their trades, but the order actually happens at independent places. What is centralized is the record of ownership of the shares. All publicly tradable shares in the US are in a technical sense owned by Cede & Co., a partnership related to the DTCC. When shares change hands, all that happens is an entry in the database at the DTC. Since we're talking about the blockchain, it's interesting to know how this system is secured. The mechanism is that both parties report the expected transactions to DTCC, which ensures they match before the money changes hands. The trade that happens during market hours is only the agreement to trade, and the actual delivery happens three days later.