8. lic-he has no standing to demand an interference with any other applicant or with a patentee. parte Abbey, MS. D. 1890, p. 304. Ex Where a question as to the patentability of the invention in issue is raised by some tribunal of the Patent Office after the declaration of an interference, Held that it should be finally settled before a decision on priority is rendered which entitles the defeated party to appeal to the court. Oliver v. Felbel, 100 O. G., 2384; C. D., 1902, 565; 20 App. D. C., 255. Where, however, a question of patentability was raised in an interference involving an application and a patent, the Court of Appeals suggested that it might have been better to have assumed patentability, as claims in contest had already been granted to the patentee. The court in that case, however, sus stained the Office ruling that the claims in question were unpatentable. In re Orcutt, 141 O. G., 567; C. D., 334; 32 App. D. C., 345. the 1909. The same position was taken by Commissioner Ewing in ex parte Brinkman, 112 MS. D., 128 (Jan. 8, 1914), wherein he said: * * * it seems to me clear that after a patent has once been granted it is not good practice to reject an ap plicant seeking an interference, where the rejection is based upon no clear anticipation, but the piecing together of sev The policy of this decision was reaffirmed by the present Commissioner, Newton, then Assistant Commissioner in Both v. Barr 200 O. G., 582; C. D., 29. See also the last paragraph of Rule 95. 1914. The practice set forth in that part of Rule 93 which authorizes ascertainment from a prior party of his date of conception in order to ascertain whether any question of priority arises, embodies a wide departure from the old rule and is based upon the decision of Ewing, Commissioner of Patents v. U. S. ex rel Fowler Car Co., 224 U. S., 1; 238 O. G., 983; C. D., 1917. 409. The correspondence necessary to carry this part of the rule into effect is handled by the Law Examiner over the Commissioner's signature and copies there of are preserved in the Commissioner's files. When a junior party reports a date of conception later than the filing date of a senior party ordinarily the proposed interference is disapproved, the senior application is passed to issue, the senior applicant is invited to promptly pay the final fee to the end that his patent may be made available for citation as a reference against a later filed application. In the meantime the junior party's application is withheld temporarily and as soon as the senior party's patent appears claims in the junior party's application are rejected thereon in so far as they are found to be anticipated thereby, as in the case of any other prior art. 9. The last clause of Rule 93 provides a means whereby both claimants may be placed in a position for final adjudication of their conflicting claims in a court of equity under section 4918 R. S., which provides for interference contests between patentees. 1. RULE 94. 94. Interferences will be declared between applications by different parties for patent or for reissue when such applications contain claims for substantially the same invention which are allowable2 in the application of each party, and interferences will also be declared between applications for patent, or for reissues and unexpired original or reissued patents, of different parties, when such applications and patents contain claims for substantially the same invention which are allowable in all of the applications involved: Provided, That where the filing date of any applicant is subsequent to the filing date of any patentee, the applicant shall file an affidavit that he made the invention before the filing date of the patentee.4 Parties owning applications or patents which contain conflicting claims will be required before an interference is declared to show cause why these claims shall not be eliminated from all but one of the applications or patents of common ownership.5 Interferences are declared only to determine the question of priority. Therefore an interference will not be declared between two applications of the same party assigned to different parties merely for the purpost of determining the question of title. Ex parte Pearsall, 17 Gour. 55-16. 2. When it distinctly appears that an applicant is not entitled to Letters Patent as between himself and the public, there is no precedent or principle justifying the applicant's demand that a patent be allowed to him, in order that an interference may be instituted with a patent previously granted to another. Ex parte Meucci, C. D., 1890, 65; 51 O. G., 299. Where it is apparent at the outset that no patent can issue on an application, it will not be placed in interference, since a party is not entitled to an interference except as to an allowable application. Ex parte Crane, 106 O. G., 999, C. D., 1903, 332, and to the same effect are: Neill v. Commissioner of Patents, 82 O. G., 749; C. D., 1898, 332; Oliver v. Felbel, 100 O. G., 2384; C. D., 1902, 565. Section 9 of former Rule 94, which was replaced by present Rule 94, reads as follows: "An interference will not be declared between an original application filed subsequent to December 31, 1897, and a patent issued more than two years prior to the date of filing of such application or an application for the reissue of such a patent." In certain cases parties may be claiming substantially the same invention and still it may not be proper to suggest claims as provided by Rule 96. For example, one of the parties may be estopped by his conduct from making claim to such invention or the question of priority between the parties may be res adjudicata by virtue of a prior interference involving them or those in privity with them. For a summary of the law dealing with the subject of res adjudicata see a paper read before the examining corps by Examiner-in-Chief Fairfax Bayard, June 30, 1915. A party to an interference, having conceded priority of invention to his opponent in general terms, and a patent having issued in accordance with his concession and request, is estopped from claiming a new interference with the same party on the subject-matter common to the two applications Harlow v. Guernsey, C. D., 1875, p. 47; 7 O. G., 513. Again it may happen that the claim of an unexpired domestic patent may be improperly copied or suggested to an applicant for interference purposes. A recent line of decisions bearing on this class of cases is headed by Rowntree v. Sloan, 45 App. D. C., 207; 227 O. G., 744. In that case an applicant had failed to copy the claims of a patentee within three years from the date of issuance of the patent and the court held that by his laches, in failing to make the claims within a reasonable time after the patent issued, he was estopped from making such claims at all. As an indication of what it considered a reasonable time for making claims under such circumstances the court said: "If he thought these claims read upon his application, it was his duty promptly to make them, at least within the time allowed for amendment after office action, and his failure to do so is fatal to his present contention." The court also said: "We have not overlooked his contention that there were claims in his application as originally filed approximating the claims of the issue. It is enough to say that we are clearly of the opinion that this contention is not justified by the record." The decision does not show that Sloan (the applicant), had actual notice of Rowntree's patent until he presented the claims, although he had of course legal constructive notice thereof. This decision was discussed at length and construed by Commissioner Ewing in the case of Wintroath v. Chapman and Chapman, MS. Dec., Vol. 123, p. 183. He therein argued, from analogy to other sections of the statute, that the time limit designated by the court within which an applicant must present the claims of a patent with which he seeks to go into interference, or be held estopped, should have been fixed by the court as two years instead of one. He then specified the following procedure for the examiner in cases where this time limit had been exceeded: "Under this rule, the primary examiner should deny the right of an applicant to make a claim taken from a patent where the period of delay exceeds two years, and declare an interference only where a prima facie case overcoming the charge of dilatoriness is made out by the applicant. Such a showing would of course be open to attack inter partes." This case was appealed to the Court of Appeals, and in a decision by the Chief Justice of that Court rendered March 4, 1918, the Court said: "We * * = adhere to the ruling in the Rowntree case, but with this modification however:-the period should be one year unless the applicant shall satisfy the Commissioner that the delay was unavoidable. This brings the holding into closer harmony with the statute governing amendments (R. S., Sec. 4894) than is done by the Rowntree case." The case of Wintroath vs. Chapman and Chapman was carried by writ of certiorari to the Supreme Court of the United States, which on March 1, 1920, reversed the decision of the Court of Appeals. The final paragraph of the decision of the Supreme Court reads: As has been pointed out, the Examiner of Interferences did not permit the introduction of any evidence with respect to laches or abandonment and the Court of Appeals rests its judgment, as he did, wholly upon the delay of the Chapmans in filing their divisional application for more than one year after the Wintroath patent was issued, as this appeared "on the face of the record." While not intending to intimate that there may not be abandonment which might bar an application within the two-year period allowed for filing, yet upon this discussion of the statutes and decisions, we cannot doubt that upon the case disclosed in this record, the Chapmans were within their legal rights in filing their divisional application at any time within two years after the publication of the Wintroath patent, and therefore the judgment of the Court of Appeals must be Reversed. In the case of Ex parte Rosenthal, MS. Dec., Vol. 123, p. 299, which preceded the decision by the Court of Appeals D. C., but followed that of Com. Ewing in the Wintroath v. Chapman and Chapman case, Assistant Commissioner Whitehead allowed an applicant to present the claims of a patent more than two years after the patent issued in view of the fact that he found that the applicant had been claiming substantially the same invention within the two year period. He said: "* if the examiner's atten * tion had been called to the patent it would have been his duty to notify the applicant that he could not be allowed the claim in question except upon establishing priority in an interference to be declared upon claims copied from the patent. Under these circum |