delivered tbe opinion of the court:
This is an appeal in an interference proceeding from the decision of the Board of Interference Examiners of the United States Patent Office awarding priority of invention of the. subject matter defined by the counts in issue (Nos. 1 to 6, inclusive) to appellee, Claude D. Hayward.
The interference is between appellants’ patent, No. 2,240,699, issued May 6,1941, on an application filed November 12,1938, and appellee’s application, serial No. 339,096, filed June 6,1940.
In appellee’s involved application it is stated that—
This application is a continuation-in-part of my eopending application, Ser. No. 179,016, filed December 9, 1937, for Protection of Electric Systems, the subject matter of said prior application being incorporated in this application together with additional subject matter.
It appears that appellee’s earlier application, serial No. 179,016, filed December 9, 1937 (referred to in the quoted excerpt from ap-pellee’s involved application), containing 24 claims, was allowed by the Primary Examiner; that notice of allowance of that application was issued on May 14, 1940; and that approximately three weeks after the notice of allowance appellee filed his continuation-in-part application here involved. Subsequent to the filing of his continuation-in-part application, appellee’s allowed application became forfeited by his failure to pay the final fee.
It will be observed from what has been said that appellee’s allowed application and his continuation-in-part application were copending in the Patent Office, and that each of these applications was copending Avith appellants’ ■ application which matured into their involved patent.
On June 10,1942- an interference was declared between appellants’ patent and appellee’s application (No. 339,096).
*1054On September 5,1942, appellee moved to shift the burden of proof, claiming that he was entitled to the filing date of his earlier application for conception and constructive reduction to*practice of the invention defined by the counts of the interference.
Appellants opposed the motion to shift the burden of proof for the reason, among others, that as appellee’s involved application was filed after the allowance of his earlier application, he was not entitled to the filing date of his earlier application for constructive reduction to practice.
Appellee’s motion to shift the burden of proof was granted by the Primary Examiner, and appellee was made the senior party in the interference.
As the dates alleged in appellants’ preliminary statement for conception and reduction to practice of the involved invention were subsequent to the filing date of appellee’s earlier application, appellants were ordered to show cause why judgment on the record should not be rendered against them.
After reciting the facts hereinbefore stated, the Board of Interference Examiners stated that the sole issue before it was whether appel-lee was entitled to the filing date of his earlier application for constructive reduction to practice, in view of the fact that the renewal statute, section 4897 of the Revised Statutes (U. S. C. title 35, sec. 38) ’ had been repealed August 9,1939. In awarding priority of invention to appellee Hayward, the board held that the decision in the case of In re Febrey, 30 C. C. P. A. (Patents) 1099, 135 F. (2d) 751, 57 USPQ 407, where the facts were similar to the facts in the instant case, was controlling; that, therefore, appellee was entitled to the filing-date (December 9, 1937) of his earlier application (No. 179,016) for constructive reduction to practice of the invention defined by the counts in issue; and that, as that date was'prior to any date alleged by appellants, appellee was entitled to an award of priority of invention.
The sole issue before us is one of law; that is, whether appellee is entitled to the filing date of his allowed application for constructive reduction to practice.
If appellee is entitled to the filing date of his allowed application for constructive reduction of the invention to practice, the decision of the Board of Interference Examiners should be affirmed. If he is not, the decision should be reversed.
The issue before us being one of law, it is unnecessary that we quote any of the counts involved or discuss the invention defined thereby.
The facts in the Febrey case, supra, stated briefly, are as follows: An application of Febrey was allowed on July 20, 1940, with two claims. Febrey did not pay the final fee and the application became forfeited January 20, 1941. However, on January 9, 1941, before his *1055application became forfeited, Febrey filed an application (which, recited that it was a continuation of his prior application) in which he presented the two claims that had been allowed together with additional claims. The Primary Examiner declined to give Febrey’s continuing application the benefit of the filing date of his allowed application, and rejected the claims on the ground that the invention defined thereby had been in public use for more than one year prior to the filing of the continuing application. In so holding, the examiner stated, in substance, that Febrey’s continuing application had been filed after the right of amendment of his original application had lapsed; that his continuing application was, in effect, a renewal of his original application; and that as the renewal statute (section 4897, supra), which authorized the filing of renewal applications after allowed applications had become forfeited, had been repealed, Febrey’s application there involved could not be regarded as a continuation of his allowed application. On appeal, the Board of Appeals affirmed the decision of the Primary Examiner.
In our decision in the Febrey case, supra, we stated that, at the time of the filing of his continuing application, Febrey’s allowed application was pending in the Patent Office, and that had the renewal statute (secton 4897, supra) not been repealed, the provision thereof would not have been applicable to the facts in the case for the reason that when Febrey’s continuing application was filed, his allowed application had not been forfeited. We there reviewed the decisions in several cases relating to continuing applications, including the case of Godfrey v. Eames, 68 U. S. 317, and, wth reference to that case, said:
Appellant relies upon the case of Godfrey v. Eames, 68 U. S. 317, decided in 1863, wherein Godfrey filed an application for a patent for an invention, the claims for which were rejected by the commisioner. At the time such application was filed, there was no bar of public use of the invention. Later Godfrey filed a new application for the same invention, but if limited to the date of his new application the bar of public use would exist. A patent was issued upon his second application.
The question there decided was that his second application should be held to be a continuation of his first application, and that he was entitled to the benefit of the date of his first application, and hence the patent was not invalid because of prior public use of the invention.
The case last cited arose under the patent laws of 1836 and 1839, which did not contain limitations respecting prosecution of applications which were found in the present patent statutes, and a distinction between that case and the one at bar is that in the instant case, appellants application had been allowed and under Rule 78, supra, he no longer had the right to amend his application, while in the cited case the right of amendment of the first application had not been terminated.
It should be noted that neither Section 4897, supra, nor any similar statute was in existence at the time of the decision in the last cited case. This section was enacted in substantially the form hereinbefore quoted.
*1056We further said, inter alia:
Section 4897, supra, had no application to allowed applications which had not become forfeited through failure to pay the final fee due upon the issue of a patent. As to all unforfeited applications the law as construed by the case of Godfrey v. flames, supra, and other cases, and applied by the Patent Office for many years, remained unaffected by the enactment of said section. We are therefore unable to see how an application which under the law and practice of the Patent Office was proper prior to the enactment of Section 4897, supra, and was not embraced in its provisions, could be affected by the repeal of that section.
and, in reversing the decision of the Board of Appeals, concluded our decision as follows:
As hereinbefore stated, we hold that the repeal of Section 4897, supra, is not relevant to the issue before us; that appellant, from September 28, 1938, the date of his first application, was continuously applying for a patent for the invention claimed, and that no public use of the invention was shown prior to the date of his first application.
Counsel for appellants here challenges the correctness of our decision in the Febreyi case, supra. It is conceded by counsel that- an applicant may file a continuing application or a continuation-in-part application at any time before the allowance of his original application. Counsel contend, however, that there is no authority, statutory or otherwise, for the filing of such applications, with the benefit of the filing date of an allowed application, subsequent to the allowance of the allowed application. The gist of the argument of counsel is stated in his brief as follows: .
The renewal-statute, section 4897, while it was in force, was the only statute which provided any “due proceeding” whereby a patent could be issued on an allowed application, other than by the payment of the final fee within the time set forth in the allowance-statute, section 4885.
Therefore, Arum a formal notice of allowance of an application, under section 4885, there was no¡ lawful way for a patent to issue on that allowed application, Except by either the payment of the final fee as and when required by section 4885, or the filing of a renewal application or petition as provided by section 4897.
This is so, because section 4885 says that “the patent shall be withheld,” if the final fee is not paid within the time specified; — and there has never been any other statute authorizing the commissioner ever to issue a patent on such a “withheld” application, except the renewal-statute, section 4897.
The renewal statute (section 4897, stvpra), repealed August 9, 1939, which, so far as the issues here are concerned, was originally enacted March 3,1865 (13 Stat. 533, Ch. CXII), read-:
Any person who has an interest in an invention or discovery, whether as inventor, discoverer, or assignee, for which a patent was ordered to issue upon the payment of the final fee, 'but who fails to malee payment thereof within siw months from the tim¡e at which it was passed and allowed, and notice thereof was sent to the applicant or his agent, shall have a right to make an application for a patent for such invention or discovery the same as in the case of an original *1057application. But such second application must he made within one year after the allowance of the original application. But no person shall be held responsible in damages for the manufacture or use of any article or thing for which a patent was ordered to issue under such renewed application prior to the issue of the patent. [Italics not quoted.]
Section 4885 of the Revised Statutes (U. S. C. title 35, sec. 41) reads:
Every patent shall issue within a period of three months from the date of the payment’ of the final fee, which fee shall be paid not later than sis months from the time at which the application was passed and allowed and notice thereof was sent to the applicant or his agent; and if the final fee is not paid within that period the patent shall be withheld: Provided, however, That the Commissioner ■of Patents may in his discretion receive the final fee if paid within one year after the six months’ period for payment has passed and the patent shall issue. .[Beginning with the word “may,” italics ours.]
With the exception of the proviso','which was added August 9, 1939 {53 Stat. 1293), at the time of the repeal of section 4897, supra, section 4885, supra, so far as the issues here are concerned, has been in existence since March 3, 1863 (12 Stat. 796, sec. 3).
It is so obvious as to require no discussion that the renewal statute (section 4897, supra) related solely to forfeited applications, and, as held in the Febrey case, supra, “had no application to allowed ¡applications which had not become forfeited through failure to pay the final fee.” [Italics not quoted.] Accordingly, the repeal of that statute could not in any way affect the practice in the Patent Office, permitting applicants to file continuing applications or continuation-in-part applications after allowance, but before forfeiture, of their •original applications.
It will be observed that the first part of section 4885, supra, which, as hereinbefore noted, has been in existence since 1870, provides that upon allowance of an application and notice thereof given, the applicant shall pay the final fee within six months, and that if the fee is not paid “the patent shall be withheld.” That part of section 4885 clearly provides that a patent shall not issue on a forfeited application, that is, an application which has been allowed and has become forfeited by failure of the applicant to pay the final fee within the six months’ period provided therein. There is nothing in those provisions, either express or implied, which prohibits the filing of a -continuing application or a continuation-in-part application after allowance, but before forefeiture, of an original application.
At the time of the repeal of section 4897, supra, the Congress, realizing that the provisions of section 4885, then in force, prohibited the issuance of patents on forfeited applications, added the proviso to that section which authorizes the Commissioner of Patents, in his discretion, to issue a patent on a forfeited, application, provided the final fee is paid within one year after forfeiture. It is clear, therefore, that the *1058Congress was fully aware of the fact that the first part of section 4885, so far as it prohibited the issuance of patents, applied solely to forfeited applications.
Furthermore, it has been the practice in the Patent Office for more than 50 years (much of the life of the first part of section 4885), which practice has been approved by the courts, for applicants to file continuing applications for continuation-in-part applications after allowance, but before forfeiture, of their original applications. See Dederick v. Fox, 56 Fed. 714 (decided by the Circuit Court, Western District, Pennsylvania, February 7, 1893, patent involved issued in 1888); Ex parte Lewis and Unger, 1903 C. D. 303; Gillette Safety Razor Co. v. Clark Blade & Razor co., 187 Fed. 149, 155 (decided by the Circuit Court, District New Jersey, May 8, 1911), affirmed by the Circuit Court of Appeals (Third Circuit), Clark Blade & Razor Co. v. Gillette Safety Razor Co., 194 Fed. 421; Motologue Advertising Corp. et al. v. Electric Corp., 5 USPQ 370, 379 (decided by the District Court, Eastern District, New York, May 20, 1930). See also Ex parte Buehler, 1925 C. D. 24, where the Commissioner of Patents, in holding that an applicant might forfeit an application under section 4897, supra, prior to the expiration of the six months’ period provided therein and file a reneioal application, stated, inter alia:
* * * It may be noted that the same result would be accomplished if the applicant should file a new application for the same invention, and therefore abandon the second application. The Government fee would be the same in both cases ; but the applicant would be put to the expense of preparing new papers and there would be a duplication of the Patent Office records. No necessity is seen for requiring such additional expense and duplication of records. [Italics net quoted.]
It is evident from the quoted excerpt from the decision in the Buehler case, supra, that the commissioner had in mind that an applicant had a right to file a continuing application or a continuation-in-part application after allowance, but before forfeiture, of his original application, and that such an • application would be entitled to the filing date of his allowed application.
The decisions in the above cited cases were not based upon the provisions of -the renewal statute (section 4897, supra), as it is obvious they could not have been, but rather upon the premise [3] that an allowed application, not forfeited, is pending in the Patent Office, and that there is continuity between such application and a continuing application or a continuation-in-part application.
We are of opinion that neither the renewal statute (section 4897, supra) nor the first part of section 4885, supra, ever had any bearing whatsoever upon the right of an applicant to file a continuing-application or a continuation-in-part application after allowance, but before forfeiture, of an original application.
*1059Counsel for appellants argues that the case of Godfrey v. Eames, supra, does not hold that a continuing application or a continuation-in-part application may'be filed subsequent to the allowance of an original application and, apparently, is of the view that we held that it did in the Febrey case, supra.
We did not so hold, as is apparent from our decision in the Febrey case, supra. However, as appears from the quoted excerpt from our decision in that case, we stated that section 4897, supra, related solely to forfeited applications; that the law as to unforfeited applications, as construed in the case of, Godfrey v. Eames, supra, and other cases, and as applied by the Patent Office for many years, remained unaffected by the enactment of that section; and that as the law applicable to unforfeited applications was not affected by the enactment of that section, we were unable to understand how it could be affected by the repeal of that section.
It is argued that the repeal of the renewal statute was for the purpose of preventing long delay in the issuance of patents, and that the purpose of the Congress would be thwarted should it be held that a continuing or a continuation-in-part application might be filed as a matter of right after the allowance, but before forfeiture, of an original application.
It has not been questioned here that a continuing or a continuation-in-part application may be filed at any time prior to the allowance of an original application. Furthermore, it has been the practice in the Patent Office for applicants to file continuing or continuation-in-part applications prior to the allowance of original applications as a matter of right, and that practice has continued in the Patent Office since the repeal of the renewal statute (section 4897, supra). See Ex parte Silver, 50 USPQ 519; Ex parte Davidson, 58 USPQ 343.
It is obvious, therefore, that if a continuing or a continuation-in-part application may be filed as a matter of right up to the time of the allowance of an original application, the right to file such an application, after allowance but before forfeiture of an original application, would not be extended for a period greater than six months.
But one other mhtter remains to be considered. It has been suggested that continuing applications and continuation-in-part applications must be considered as amendments of original applications; that the only authority for amending allowed applications which have not become forfeited is provided for in rules 78 and 165 of the Pules of Practice in the United States Patent Office; and that amendments to such applications, whether by continuing applications or continuation-in-part applications or otherwise, may be made only when approved by the Commissioner of Patents. Those rules, which *1060were in existence for more than 50 years prior to the repeal of section 4897, sufra, read:
78. Amendments after the notice of allowance Of an application will not be permitted as a matter of right, but may be made, if the specification has not been printed, on the recommendation of the primary examiner, approved by the Commissioner, without withdrawing the case from issue. (See rule 165.)
165. After notice of the allowance of an application is given, the case will not be withdrawn, from issue except by approval of the Commissioner, and if withdrawn for further action on the part of the office a new notice of allowance will be given. When the final fee has been paid upon an application for letters patent, and the case has received its date and number, it will' not be withdrawn from issue on account of any mistake or change of purpose of the applicant, his attorney or his agent, nor for the purpose of enabling the inventor to procure a foreign patent, nor for any other reasons except mistake on the part of the office, or because of fraud, or illegality in the application, or for interference. (See rule 78.)
Assuming for the- purpose of this decision, without holding, that a continuing application or a continuation-in-part application is an amendment of an allowed application, it is not an amendment of the kind contemplated by rules 78 and 165, supra. The amendments contemplated by those rules are amendments which are entered in the files of allowed applications and become physical parts thereof; whereas continuing applications and continuation-in-part applications are separate applications which do not form physical parts of allowed applications, although they are accorded the benefit of the filing dates of such allowed applications as to all common subject matter. That those rules were not intended to apply to continuing applications or continuation-in-part applications, is evidenced by the fact that, although they were in force for more than 50 years prior to the repeal of section .4897, supra, it was the practice in the Patent Office during that period for applicants to file continuing applications or continuation-in-part applications of allowed, but not forfeited, applications as a matter of right.
We adhere to the views expressed in our decision in the case of In re Febrey, supra.
For the reasons stated, the decision of the Board of Interference Examiners is affirmed.