SMYTH, Chief Justice.
From a decision of the First Assistant Commissioner of Patents, awarding priority to Kennington with respect to the invention of the issue, Bijur appeals.
The structure involved is described in four counts, illustrated sufficiently by count 1, which reads:
A starter for gas engines and the like, comprising in combination with a member operatively connected with the engine, a motor, a shaft driven thereby, a driving member adapted to engage and drive the engine member but normally out of engagement therewith, said driving member being mounted on the shaft and having screw-threaded engagement therewith whereby rotation of the shaft advances such driving member into engagement with the engine memner, and means for yieldingly stopping said driving member and thus permitting it to yield and cushion the shock of starting the engine member.
[1, 2] The three tribunals of the Patent Office concurred in favor of Kennington. Were they clearly wrong? If not, we must affirm the commissioner's decision. Ruth v. Groch, - App. D. C. -, 277 Fed. 861, and cases cited therein. Bijur does not deny that Kenning-ton conceived in January, 1912, but insists he did not actually reduce to practice until October, 1913. Kennington urges that he is entitled to May 24, 1912, for reduction to practice, because he and one McDer-mott filed a joint application on that date for the invention of the issue. Later it was decided that this application was not allowable, for the reason that Kennington was the sole inventor of the subject-matter disclosed. Kennington then filed the present application. Bijur says that he is not entitled to the filing date of the joint application, but must he confined to that of the present one, March 13, 1915.
We held in Re Roberts, 49 App. D. C. 250, 263 Fed. 646, that the sole inventor was entitled to the benefit of the date of the joint application, on the theory that his application was an amendment of the joint one. It is a rule that “an amendment relates back to the time of the filing of the original petition.” Union Pacific R. Co. v. Wyler, 158 U. S. 285, 296, 15 Sup. Ct. 877, 882 ( 39 L. Ed. 983). From this it follows that Kennington is entitled to May 24, 1912, for constructive reduction to practice.
[3] The present application of Bijur was involved in Halbleib v. Bendix, 50 App. D. C. 247, 270 Fed. 683. He there relied on a device described as Exhibit 2 for reduction to practice, which he said took place in the early part of 1912. He stands on the same exhibit here and the same reduction to practice. In that case he contended that the device was tested on a Packard car, which had been furnished for that purpose by the Packard Company, and he presented the testimony of a number of witnesses to support his position. We held that, if his conduct after that test was such as to corroborate his proof concerning it, “reduction to practice could be readily inferred; but it was not.” His conduct, we said, forced the conclusion that what he had done on the car in 1912 was an “abandoned experiment.” We further said that he made no attempt after that to do anything with the device until January or February, 1914. The testimony which Bijur presents in this case somewhat strengthens the testimony in the former one, but that avails him nothing, because, as we have just said, the decision there rested, not upon the testimony of his witnesses, but *315upon his own conduct after llie test, which we held clearly established that lie did not regard the “test as a success.” Nothing that he has produced in this case lessens the probative force of his conduct, and therefore we must adhere to our former conclusion, namely, that he had not proven a satisfactory reduction to practice in 1912.
[4] Bijur, however, urges that the main question in this case is one of res judicata. He insists that in a prior interference, No. 38,013, between him and Kennington, the examiner of interferences held that Exhibit 2, which lie claims embodies the invention of the present issue, was actually reduced to practice in April or May, 1912, and that this decision is final, because an appeal taken from it was subsequently dented. The Examiner’s decision was offered in evidence by Bijur, but the record before us does not contain it. Without it we cannot decide that the question now presented for adjudication was disposed of by it, unless we unite the extracts which purport to have been taken from it as they appear in the opinion of the Patent Office tribunals and the briefs of the parties, and treat the result as a true copy. We have done so, and we proceed on the assumption that the copy is correct.
[5] Bijur had a constructive reduction to practice of the invention involved in that interference as of March 13, 1912. This was not denied. It was therefore entirely unnecessary for the Examiner of Interferences to decide that Bijur had actually reduced to practice at a later date. The question was not before him, and his holding was merely obiter. It is well settled that, “where the second action between the same parties is upon a different claim or demand, the judgment in the prior action operates as an estoppel only as to those matters in issue or points controverted, upon the determination of which the finding or verdict was rendered.” Cromwell v. County of Sac, 94 U. S. 351, 353 (24 L. Ed. 195); Radford v. Myers, 231 U. S. 725, 730, 34 Sup. Ct. 249, 58 L. Ed. 454. The matter presented for decision in the prior interference was as to whether Kennington’s reduction to practice preceded or followed BIjur’s dale, March 13, 1912. Whether or not Bijur had a later date was a question not in issue, and the Examiner of Interferences had no power to decide it in that proceeding.
Bijur has not established that the decision of the Commissioner of Patents is wrong, and it is therefore affirmed.
Affirmed.