TMEP § 405.04
Under 35 U.S.C. §42(d) and 37 C.F.R. §2.209, only money paid by mistake or in excess (when a fee is not required by statute or rule, or is not required in the amount paid) may be refunded. A change of purpose after the payment of money does not entitle a party to a refund. For example, if a party deletes a class from an application, or decides to no longer go forward with an application or appeal, the party is not entitled to a refund. See TMEP §711.03 regarding refunding the fee for an extension request after issuance of a supplemental Office action.
If an examining attorney or other USPTO employee erroneously requires a fee, the USPTO will refund the fee submitted in response to the erroneous requirement.
After the USPTO has processed an application or other document, the USPTO will not refund the filing fee. The USPTO will not refund an application filing fee when registration is refused, nor will it refund a fee when a timely filed document (such as a statement of use under 15 U.S.C. §1051(d) or affidavit of use or excusable nonuse under 15 U.S.C. §1058) is rejected for failure to meet the requirements of the statute and/or rules.
Refund requests should be sent to: Mail Stop 16, Director of the U.S. Patent and Trademark Office, P.O. Box 1450, Alexandria, VA 22313-1450. For more information about requesting a refund, see https://www.uspto.gov/learning-and-resources/fees-and-payment/refund-information.
When a USPTO employee determines that a refund is appropriate, the employee must submit the request to TM Finance with the information necessary for processing the refund.