28 CFR § 5.500 - Maintenance of books and records.
(a) A registrant shall keep and preserve in accordance with the provisions of section 5 of the Act the following books and records:
(1) All correspondence, memoranda, cables, telegrams, teletype messages, and other written communications to and from all foreign principals and all other persons, relating to the registrant's activities on behalf of, or in the interest of any of his foreign principals.
(2) All correspondence, memoranda, cables, telegrams, teletype messages, and other written communications to and from all persons, other than foreign principals, relating to the registrant's political activity, or relating to political activity on the part of any of the registrant's foreign principals.
(3) Original copies of all written contracts between the registrant and any of his foreign principals.
(4) Records containing the names and addresses of persons to whom informational materials have been transmitted.
(5) All bookkeeping and other financial records relating to the registrant's activities on behalf of any of his foreign principals, including canceled checks, bank statements, and records of income and disbursements, showing names and addresses of all persons who paid moneys to, or received moneys from, the registrant, the specific amounts so paid or received, and the date on which each item was paid or received.
(6) If the registrant is a corporation, partnership, association, or other combination of individuals, all minute books.
(7) Such books or records as will disclose the names and addresses of all employees and agents of the registrant, including persons no longer acting as such employees or agents.
(8) Such other books, records, and documents as are necessary properly to reflect the activities for which registration is required.
(b) The books and records listed in paragraph (a) of this section shall be kept and preserved in such manner as to render them readily accessible for inspection pursuant to section 5 of the Act.
(c) A registrant shall keep and preserve the books and records listed in paragraph (a) of this section for a period of 3 years following the termination of his registration under § 5.205.
(d) Upon good and sufficient cause shown in writing to the Assistant Attorney General, a registrant may be permitted to destroy books and records in support of the information furnished in an initial or supplemental statement which he filed 5 or more years prior to the date of his application to destroy.