What happens if an amendment is unsigned or improperly signed?

An unsigned amendment or one not properly signed by a person having authority to prosecute the application is not entered into the application. The MPEP states: An unsigned amendment or one not properly signed by a person having authority to prosecute the application is not entered. (MPEP 714.01(a))

The examiner will notify the applicant of the status of the application and advise them to either furnish a properly signed duplicate amendment or ratify the amendment already filed. In applications not under final rejection, applicants are typically given a two-month time period to ratify the previously filed amendment, as per 37 CFR 1.135(c).

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Tags: patent application, USPTO procedure