What is an S-signature and how should it be used in USPTO correspondence?

An S-signature is a type of electronic signature used in USPTO correspondence. According to MPEP 501, which cites 37 CFR 1.4(d)(2):

An S-signature is a signature inserted between forward slash marks, but not a handwritten signature as defined by paragraph (d)(1) of this section. An S-signature includes any signature made by electronic or mechanical means, and any other mode of making or applying a signature other than a handwritten signature.

Key requirements for an S-signature include:

• It must consist only of letters, Arabic numerals, or both, with appropriate punctuation.
• The signer must insert their own S-signature with a single forward slash mark before and after the signature.
• For patent practitioners, their registration number must be included with or near the S-signature.
• The signer’s name must be presented in printed or typed form near the S-signature.

Example of a proper S-signature: /John D. Smith/

S-signatures can be used for most USPTO correspondence filed electronically or by facsimile.

For more information on USPTO correspondence, visit: USPTO correspondence.