Section 4903. Whenever, on examination, any claim for a patent is rejected, the Commissioners shall notify the applicant thereof, giving him briefly the reasons for such rejection, together with such information and references as may be useful in judging of the propriety of renewing his application or of altering his specification; and if, after receiving such notice, the applicant persists in his claim for a patent, with or without altering his specifications, the Commissioner shall order a re-examination of the case.

The rule requiring the Commissioner of patents to set forth the grounds of his decision fully in writing must be strictly followed.37 If the matter has not been finally disposed of in the patent office an application is always open to amendment.38