37 C.F.R. § 2.206 Trademark fees payable in advance.
Title 37 - Patents, Trademarks, and Copyrights
(a) Trademark fees and charges payable to the Office are required to be paid in advance; that is, at the time of requesting any action by the Office for which a fee or charge is payable. (b) All fees paid to the Office must be itemized in each individual trademark application or registration file, or trademark proceeding, so that the purpose for which the fees are paid is clear. The Office may return fees that are not itemized as required by this paragraph.
Title 37: Patents, Trademarks, and Copyrights
PART 2—RULES OF PRACTICE IN TRADEMARK CASES
Fees and Payment of Money in Trademark Cases
§ 2.206 Trademark fees payable in advance.
