Trademark Rule 2.193(c), 37 C.F.R. §2.193(c), sets forth the requirements for electronic signatures for trademark correspondence. Under Rule 2.193(c), a person signing a submission electronically must either:

1. (1) Personally enter any combination of letters, numbers, spaces, and/or punctuation marks that the signer has adopted as a signature, placed between two forward slash ("/") symbols in the signature block on the electronic submission; or
2. (2) Sign the document using some other form of electronic signature specified by the Director.

37 C.F.R. §2.193(c).

In accordance with the Director’s discretion to specify other forms of acceptable electronic signatures under Rule 2.193(c)(2), 37 C.F.R. §2.193(c)(2), as of July 22, 2023, the USPTO began accepting documents with electronic signatures generated via third-party document-signing software, provided the signature meets the requirements set forth in TMEP §611.01(c)(ii). The Director has not specified any other form of acceptable electronic signature under Rule 2.193(c).