27 CFR 26.62: Corporate surety.

(a) Surety bonds may be given only with corporate sureties holding certificates of authority from, and subject to the limitations prescribed by, the Secretary of the Treasury of the United States, as set forth in the current revision of U.S. Treasury Department Circular 570 (Companies Holding Certificates of Authority as Acceptable Sureties on Federal Bonds and as Acceptable Reinsuring Companies).

(b) U.S. Treasury Department Circular 570 is published in the Federal Register annually on the first business day in July, and supplemental changes are published periodically thereafter (see https://www.federalregister.gov). The most recent circular and any supplemental changes to it may be viewed on the United States Treasury Department's Bureau of the Fiscal Service website (see https://fiscal.treasury.gov).