17 CFR § 1.26 - Deposit of instruments purchased with futures customer funds.
(a) Each futures commission merchant who invests futures customer funds in instruments described in § 1.25, except for investments in government money market funds, shall separately account for such instruments as futures customer funds and segregate such instruments as funds belonging to such futures customers in accordance with the requirements of § 1.20. Each derivatives clearing organization which invests money belonging or accruing to futures customers of its clearing members in instruments described in § 1.25, except for investments in government money market funds, shall separately account for such instruments as customer funds and segregate such instruments as customer funds belonging to such futures customers in accordance with § 1.20.
(b) Each futures commission merchant or derivatives clearing organization which invests futures customer funds in government money market funds, as permitted by § 1.25, shall separately account for such funds and segregate such funds as belonging to such futures customers. Such funds shall be deposited under an account name that clearly shows that they belong to futures customers and are segregated as required by sections 4d(a) and 4d(b) of the Act and by this part. Each futures commission merchant or derivatives clearing organization, upon opening such an account, shall obtain and maintain readily accessible in its files in accordance with § 1.31, for as long as the account remains open, and thereafter for the period provided in § 1.31, a written acknowledgment and shall file such acknowledgment in accordance with the requirements of § 1.20. In the event such funds are held directly with the government money market fund or its affiliate, the written acknowledgment shall be in the form as set out in appendix F or G to this part. In the event such funds are held with a depository, the written acknowledgment shall be in the form as set out in appendix C or D to this part. In either case, the written acknowledgment shall be obtained, provided to the Commission and designated self-regulatory organizations, and retained as required under § 1.20.