Section 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).(2)Legacy Treasury Direct®. The Legacy Treasury Direct system is a non-Internet-based book-entry system maintained by Treasury for purchasing and holding marketable Treasury securities as book-entry products. A Treasury security is maintained in Legacy Treasury Direct if it is credited to a Legacy Treasury Direct account as described in § 357.20 of this part. Treasury securities are held directly by the Department of the Treasury in accounts maintained in the investor's name. A Legacy Treasury Direct account may be accessed through a designated Federal Reserve Bank or the Bureau of the Fiscal Service. See subpart C of this part for rules pertaining to Legacy Treasury Direct.(3)TreasuryDirect®. TreasuryDirect is a book-entry, online system maintained by the Department of the Treasury for purchasing and holding eligible marketable Treasury securities, United States Savings Bonds, and certificates of indebtedness in electronic form as a computer record on the books of Treasury. The regulations governing TreasuryDirect are found at 31 CFR part 363.(b)Transferability between Legacy Treasury Direct and other systems. A Treasury security maintained in Legacy Treasury Direct may be transferred to an account in TRADES or to an account in TreasuryDirect in accordance with § 357.22(a) . Securities may not be transferred to Legacy Treasury Direct from other systems. 67 FR 64278 , Oct. 17, 2002, as amended at 70 FR 57431 , Sept. 30, 2005; 70 FR 57441 , Sept. 30, 2005; 76 FR 18063 , Apr. 1, 2011