gine. It may be that shop tests of such a ring to be used in an internal combustion engine may be sufficient to meet the requirements of law if they demonstrate the practical utility of the device for the purposes intended. What we do hold here is that Bowers' tests, under all the circumstances stated, must be regarded as insufficient. Clearly, Bowers' tests are not satisfactory with respect to the carbon removing capabilities of Exhibit 10-A, irrespective of what might be concluded as to what the tests disclosed with reference to other features of the ring. Bowers, in his application, states: A principal object of the invention is to improve oil control piston rings and to prevent deposit of carbon on such rings, with a view of maintaining oil passages of the ring open and thereby effecting savings in oil consumption and increasing the life and efficiency of combustion motors. * * [Italics ours.] [6] The results as were testified to by one or more of the witnesses might be good so far as scraping the oil from the side walls of the cylinder is concerned, but that does not meet the requirements here. Other defects might have existed. The invention here, as is apparent from all three applications, is directed to the breaking up and dispersion of carbon formation on the ring. Of course, to successfully accomplish this purpose, one would obviously want to use a ring which would not leak oil. If the inventor satisfactorily ascertains that it will not leak oil, this alone does not suffice for a showing that it will take care of the carbon problem. The utility of Bowers' ring, Exhibit 10-A, was not sufficiently shown to amount to a reduction to practice of the invention with which all three of the parties here were concerned. In support of his contention that shop tests are sufficient, Bowers has cited a number of authorities, among them, Goodale v. Lund, 25 C. C. P. A. (Patents) 1148, 96 F. (2d) 840, 37 USPQ 696. In that case it was held that certain shop tests of air valves were sufficient. Attention was called to the fact that the tests to which the valves were subjected were those generally resorted to by the inventor's company in its efforts to ascertain the commercial value and practical utility of valves for steam heating systems. Bowers, in relying upon that holding, stresses the fact that Exhibit 10-A was tested by his company in the manner in which it tested all its piston rings in order to determine their utility. But regardless of whether under certain circumstances an oil-control ring might be sufficiently tested on an air compressor in a shop to meet the requirements of law, the record in the instant case, as we have pointed out, does not show that the tests made by Bowers demonstrated the utility of Exhibit 10-A sufficiently to meet those requirements. It follows from the foregoing, therefore, that the board correctly held that neither Bowers nor Valley met the burden of proving priority over the party Ernst by a preponderance of evidence. Its decision awarding priority to Ernst of the invention of the two counts involved is accordingly affirmed. 579 O. G. 3; 32 C. C. P. A. 1047; 149 F. (2d) 942; 66 USPQ 41 BAKER, JR., ET AL. v. ALTHER (No. 4994) 1. PATENTS-REHEARING AND REOPENING ERRORS IN OPINION Court grants rehearing solely to permit it to revise language in original opinion. 2 PATENTS INTERFERENCE-REDUCTION TO PRACTICE CONSTRUCTIVE REDUCTION Where original application and its continuation were copending as were instant division with continuation of which it is division, and drawings of first two applications include drawing of division, and specifications of two earlier applications read on drawing of division, applicant is entitled to benefit of filing date of original for conception and constructive reduction to practice. 3. PATENTS-INTERFERENCE DISSOLUTION INTERFERENCE-INTERFERENCE IN FACT Party, in effect, admits that counts read on opponent's application by failure to move to dissolve. 4. PATENTS ABANDONMENT APPLICATIONS FOR PATENT CONTINUING APPLICATIONS FOR PATENT-DIVISIONAL INTERFERENCE-PRIORITY-CONCEALMENT OF INVENTION Two days before expiration of period for response to final rejection of original application (filed 1935), applicant filed continuing application (in 1939) whose claims were merely colorably different from rejected claims; specifications were substantially identical; original became abandoned; instant application was filed in 1941 as division of continuation, which was abandoned in 1943; in filing applications, applicant did what he is entitled to do under the law, and therefore it is unnecessary to discuss suppression, concealment, and abandonment. 5. PATENTS COSTS-DIMINUTION OF RECORD Supplement was added to record on appellants' motion, consented to by appellee, subject to taxation of costs; costs are taxed against appellants since supplement was not necessary to decision. United States Court of Customs and Patent Appeals, May 22, 1945 APPEAL from Patent Office, Interference No. 79,640 [Affirmed.] Pennie, Davis, Marvin & Edmonds (Louis D. Forward of counsel) for appellants. Charles M. Thomas (Clarence O. McKay of counsel) for appellee. [Oral argument March 9, 1945, by Mr. Forward and Mr. McKay] Before GARRETT, Presiding Judge, and BLAND, HATFIELD, JACKSON, and O'CONNELL Associate Judges JACKSON, Judge, delivered the opinion of the court: This is an appeal in an interference proceeding from a decision of the Board of Interference Examiners of the United States Patent Office awarding priority of the subject matter of the involved counts to appellee.1 The counts are: 1. In the production of polymerized olefins wherein a heated gaseous mixture containing a substantial amount of normally gaseous higher olefins is passed at a temperature not substantially in excess of about 550° F. in contact with a catalyst and the product resulting from the catalyzing operation is subjected to fractional separation in a stabilizing chamber to form a liquid product and a composite normally gaseous product lean with respect to its content of higher olefins, the improvement which comprises withdrawing at least a portion consisting of a controlled quantity of the composite lean gaseous product of the stabilizing operation, and introducing said portion into the catalyzing operation together with fresh heated gaseous mixture containing a substantial amount of higher olefins, whereby a predetermined concentration of higher olefins is maintained in the catalyzing operation. 2. In the production of polymerized olefins wherein a heated gaseous mixture containing a substantial amount of normally gaseous higher olefins is passed at a tempertaure not substantially in excess of about 550° F. in contact with a catalyst and the product resulting from the catalyzing operation is subjected to fractional separation in a stabilizing chamber to form a liquid product and a composite normally gaseous product lean with respect to its content of higher olefins, the improvement which comprises withdrawing at least a portion consisting of a controlled quantity of the composite lean normally gaseous product and returning said portion to the catalyzing operation, the return of said portion being so regulated as to produce a predetermined concentration of higher olefins in the catalyzing operation. On September 23, 1941, the Primary Examiner declared an interference between appellants' patent No. 2,242,771, issued May 20, 1941, on an application filed June 23, 1937, Serial No. 149,862, and an application of appellee filed July 28, 1941, Serial No. 404,273. That application is a division of application Serial No. 279,668, filed June 17, 1939, which in turn is a continuation of application Serial No. 16,309, filed April 15, 1935. The invention is sufficiently described in the counts commencing with the words "the improvement which comprises, etc." in each count. The counts are claims copied from the patent with immaterial modifications. Appellants filed a preliminary statement on November 22, 1941, the earliest date alleged therein being later than appellee's filing date. In response to an order by the Examiner of Interferences to show cause why judgment on the record should not be entered against them, appellants filed a motion to shift the burden of proof, alleging that the divisional application was not entitled to the effective filing date of April 15, 1935, when appellee's first application was filed, for the 1 This cause was originally decided by this court on April 9, 1945. Thereafter, counsel for appellants filed a petition for rehearing. The rehearing was granted solely for the purpose of permitting the court to revise certain language in its original decision to which counsel for appellant directed the court's attention. reason that the subject matter of the counts was neither disclosed nor inherent in appellee's earliest application, and that appellee was estopped to claim priority of invention in the absence of proof of conception coupled with diligence with respect to the invention, for the reason that the assignee of appellee's application had been advised prior to December 27, 1937, of successful commercial operations involving the invention by the assignee of appellants and that notwithstanding such knowledge appellee presented no claim involving the recirculation phase of the invention directly to the catalytic polymerization zone of any hydrocarbons until June 17, 1939, the date of the continuing application, and that no claim corresponding to the specific matter here in issue was made until July 28, 1941, the date of the divisional application. Appellants alleged that such delay in filing constituted prima facie evidence of abandonment and suppression of the involved subject matter and precluded an award of priority on the record in the absence of evidence rebutting such prima facie case. The Examiner of Interferences dismissed the motion as to the second ground, which he stated "sets forth matters relating to priority," but set the motion for hearing on the first ground before the Primary Examiner, who denied the motion. Another order to show cause was thereupon issued, and in response thereto appellants again requested that times be set for taking of testimony and final hearing for the same reasons alleged in the second part of their response to the original order. Thereafter such times were set. Subsequently appellee filed a motion to vacate that action, on the ground that appellants' response to the order to show cause presented no question upon which testimony is permissible. The Examiner of Interferences, after a renewal of that motion by appellee, vacated his action in view of the express waiver of appellee's right to take testimony. Thereafter appellants moved to reset the times for taking testimony and final hearing, supporting their motion by an affidavit of one of the appellants alleged to support a charge of abandonment, suppression and estoppel and precluding an award of priority to appellee under the doctrine of Mason v. Hepburn, 13 App. D. C. 86. In his decision on that motion the Examiner of Interferences pointed out that all of the acts referred to therein and in the affidavit took place subsequent to appellee's earliest filing date, April 15, 1935, and stated that if upon final hearing that record date stands there was no possibility that any testimony by appellants with respect to concealment or suppression under the Mason v. Hepburn doctrine would have any pertinency, relevancy or utility with respect to priority, and conversely if appellee at the final hearing was held not to be entitled to his earliest date for constructive reduction to practice appellants would be awarded priority on their filing date and testimony would be futile. The examiner stated that if appellee disclosed the invention defined by the counts in his earliest application and could relate back to that date, the suppression doctrine could not be applied for the reason that appellee would be the first of the parties to take steps to place the invention before the public. The motion of appellants was dismissed. The Board of Interference Examiners thereafter awarded priority of invention of the subject matter of the counts to appellee. Appellants in their brief state that the two principal questions to be determined on this appeal are, first, does the first application of appellee disclose the subject matter in Issue, and, second, assuming that it does contain such disclosure, is appellee entitled to the benefit of the filing date of his earliest application for a constructive reduction to practice or do his actions "under the very unusual circumstances here prevailing" establish prima facie such a suppression as would deprive him of the right to assert priority of invention? It appears that the drawings in appellee's first application and his continuing application are identical, and that both include the drawing of the last-filed divisional application as part thereof line for line, letter for letter, number for number, and that the specifications of the two former applications with respect to the drawing of the last-filed application read directly thereon. The claims of the first application were finally rejected and two days before the expiration of the period for response thereto the second or continuing application was filed, the claims thereof, according to appellants, being merely colorably different from those of the first application. The two applications were substantially identical in their specifications except that the second was termed a continuing application. For the reason that the time for appeal from the rejection of the claims of the first application expired, it became abandoned, but the continuing application was still alive and had been copending with the first application. The claims of the continuation were finally rejected by the Primary Examiner, from which rejection an appeal was taken to the Board of Appeals on July 29, 1941. In view of new grounds of rejection the Primary Examiner withdrew the final rejection and after amendments had been submitted, on September 19, 1942, again finally rejected the claims. No appeal was taken from that decision and the continuing application became abandoned on March 20, 1943. The divisional application was filed July 28, 1941, and was therefore copending with the continuing application. [2] There can be no question in view of the copendency of each of the latter applications with the former application that appellee is |