Rule 312 Amendment [Patent] Law and Legal Definition

Rule 312 Amendment is an amendment submitted to the U.S. Patent and Trademark Office after the Patent Trademark Office has mailed notice of a patent application's approval. The rule regarding the amendment is codified at 37 CFR 1.312. No amendment may be made as a matter of right in an application after the mailing of the notice of allowance. Once a notice of allowance has been mailed, prosecution of the application is closed on the merits, and the entry of any amendment is within the discretion of the patent examiner. Minor amendments like correcting formal matters in the specification or drawings, change the claims without changing their scope, or cancel a claim are typically approved by the Office. However, amendments of greater significance require approval of the supervisory examiner under policies established by the group director. Usually amendments are made after allowance to amend the specification or claims, to make changes in the drawings or the list of inventors, and the submission of prior art.