19 CFR § 111.36 - Relations with unlicensed persons.
(a) Employment by unlicensed person other than importer. When a broker is employed for the transaction of customs business by an unlicensed person who is not the actual importer, the broker must transmit to the actual importer either a copy of his bill for services rendered or a copy of the entry, unless the merchandise was purchased on a delivered duty-paid basis or unless the importer has in writing waived transmittal of the copy of the entry or bill for services rendered.
(b) Service to others not to benefit unlicensed person. Except as otherwise provided in paragraph (c) of this section, a broker must not enter into any agreement with an unlicensed person to transact customs business for others in such manner that the fees or other benefits resulting from the services rendered for others inure to the benefit of the unlicensed person.
(i) A true copy of his brokerage charges if the fees and charges are to be collected by or through the forwarder, unless this requirement is waived in writing by the importer or other party in interest; or
(ii) A statement of his brokerage charges and an itemized list of any charges to be collected for the account of the freight forwarder if the fees and charges are to be collected by or through the broker;
(3) No part of the agreement of compensation between the broker and the forwarder, nor any action taken pursuant to the agreement, forbids or prevents direct communication between the importer or other party in interest and the broker; and
(4) In making the agreement and in all actions taken pursuant to the agreement, the broker remains subject to all other provisions of this part.