§ 357.0 Book-entry systems.
(a) Treasury securities. Treasury securities are maintained in one of the following book-entry systems:
(1) Commercial book-entry system. The commercial book-entry system is the book-entry system in which Treasury securities are held in a tiered system through securities intermediaries such as financial institutions or brokerage firms. A Treasury security is maintained in the commercial book-entry system if it is credited by a Federal Reserve Bank to a Participant's Securities Account. The regulations governing the commercial book-entry system are found at subpart B of this part, and are referred to as Treasury/Reserve Automated Debt Entry System (TRADES).