31 C.F.R. § 510.508
(a) Professional fees and incurred expenses. Receipt of payment of professional fees and reimbursement of incurred expenses for the provision of legal services authorized pursuant to § 510.507(a) to or on behalf of the Government of North Korea, the Workers' Party of Korea, any other person whose property and interests in property are blocked pursuant to § 510.201(a) or any further Executive orders relating to the national emergency declared in Executive Order 13466 of June 26, 2008, or any person in North Korea, or in circumstances in which the benefit is otherwise received in North Korea, is authorized from funds originating outside the United States, provided that the funds received by U.S. persons as payment of professional fees and reimbursement of incurred expenses for the provision of legal services authorized pursuant to § 510.507(a) do not originate from:
(b) Reports.
(1) U.S. persons who receive payments pursuant to paragraph (a) of this section must submit annual reports no later than 30 days following the end of the calendar year during which the payments were received providing information on the funds received. Such reports shall specify:
(ii) If applicable:
(2) The reports, which must reference this section, are to be submitted to OFAC using one of the following methods:
Note 1 to paragraph (a): Nothing in this paragraph (a) authorizes payments for legal services using funds in which any other person whose property and interests in property are blocked pursuant to § 510.201(a), any other part of this chapter, or any Executive order has an interest.