Regulations Requiring Additional Records to be Made and Retained by Dealers in Foreign Exchange (31 CFR 1022.410).

A currency dealer or exchanger must make and maintain a record of the taxpayer identification number of certain persons for whom a transaction account is opened or a line of credit is extended, and must maintain a list containing the names, addresses, and account or credit line numbers of those persons from whom it has been unable to secure such information. A currency dealer or exchanger must retain the original or a copy of certain documents, as specified in section 1022.410. The required records must be maintained for five years (31 CFR 1010.430).

The latest form for Regulations Requiring Additional Records to be Made and Retained by Dealers in Foreign Exchange (31 CFR 1022.410). expires 2021-08-31 and can be found here.