Tex. Ins. Code § 424.155
(a) While a transaction under this subchapter is outstanding, the insurer or the insurer's agent or custodian shall maintain, as to acceptable collateral received in the transaction, either physically or through the book-entry system of the Federal Reserve, Depository Trust Company, Participants Trust Company, or another securities depository approved by the commissioner:
Added by Acts 2005, 79th Leg., Ch. 727 (H.B. 2017), Sec. 1, eff. April 1, 2007.