35 U.S.C. § 42

(a) All fees for services performed by or materials furnished by the Patent and Trademark Office will be payable to the Director. (b) All fees paid to the Director and all appropriations for defraying the costs of the activities of the Patent and Trademark Office will be credited to the Patent and Trademark Office Appropriation Account in the Treasury of the United States. (c) (1) To the extent and in the amounts provided in advance in appropriations Acts, fees authorized in this title or any other Act to be charged or established by the Director shall be collected by and shall, subject to paragraph (3), be available to the Director to carry out the activities of the Patent and Trademark Office. (2) There is established in the Treasury a Patent and Trademark Fee Reserve Fund. If fee collections by the Patent and Trademark Office for a fiscal year exceed the amount appropriated to the Office for that fiscal year, fees collected in excess of the appropriated amount shall be deposited in the Patent and Trademark Fee Reserve Fund. To the extent and in the amounts provided in appropriations Acts, amounts in the Fund shall be made available until expended only for obligation and expenditure by the Office in accordance with paragraph (3). (3) (A) Any fees that are collected under this title, and any surcharges on such fees, may only be used for expenses of the Office relating to the processing of patent applications and for other activities, services, and materials relating to patents and to cover a proportionate share of the administrative costs of the Office. (B) Any fees that are collected under section 31 of the Trademark Act of 1946, and any surcharges on such fees, may only be used for expenses of the Office relating to the processing of trademark registrations and for other activities, services, and materials relating to trademarks and to cover a proportionate share of the administrative costs of the Office. (d) The Director may refund any fee paid by mistake or any amount paid in excess of that required. (e) The Secretary of Commerce shall, on the day each year on which the President submits the annual budget to the Congress, provide to the Committees on the Judiciary of the Senate and the House of Representatives— (1) a list of patent and trademark fee collections by the Patent and Trademark Office during the preceding fiscal year; (2) a list of activities of the Patent and Trademark Office during the preceding fiscal year which were supported by patent fee expenditures, trademark fee expenditures, and appropriations; (3) budget plans for significant programs, projects, and activities of the Office, including out-year funding estimates; (4) any proposed disposition of surplus fees by the Office; and (5) such other information as the committees consider necessary.