(dissenting).
The two cases upon which the majority relies to the effect that the affidavit here in issue is not properly before the court were rendered obsolete by the action of the commissioner when he abolished the rule of those cases and all of the red tape which its enforcement entailed in the tribunals of the Patent Office.
This court has otherwise regarded an affidavit submitted on a petition for reconsideration as cumulative argument of the same character as that of the request for reconsideration and has accepted the argument thus advanced in the affidavit as a ground of reversal of the board on the question of patentability.1 There is no reason why an applicant should claim a detail obvious to any person skilled in the art, and the majority in the enforcement of such a requirement here has merely made an unsupported guess.2
The specification and the claims describe heating the condensation product with an alkaline polysulfide. The exact degree of temperature to which the product must be raised to effect the reaction was not given, however, either in the claims or in the illustrative example disclosed in the specification as to how appellant obtains the final reaction product. Therefore, the examiner, among other things, rejected all of the claims as indefinite, for the stated reason that under the well known language of R.S. § 4888 appellant’s application, “in failing to mention any specific temperature, does not constitute the full, clear, concise and exact disclosure which would enable a person skilled in the art to practice the invention without further research or experimentation.”
The claims were also rejected by the examiner as unpatentable over the disclosure of the art of record; the British patent to Groves, of December 15, 1936. Groves stated that: “According to this invention viscous to caoutchouc-like products are obtained by the condensation of a thiodiglycol * * * with a dicarboxylic acid, a poly-carboxylic acid or a hydroxypolycarboxylic acid, or with an anhydride or ester of any of these acids.” The examiner held that: “In view of the breadth of the term ‘alkaline polysulfide’ it is considered that the polysul-fide glycols in Groves or esters first formed therewith are alkaline to some degree or are equivalents at least, of alkaline polysulfides. Carrying out the reaction in aqueous medium is not seen to be a patentable distinction.”
The Board of Appeals affirmed the decision of the examiner, explaining, however, that in so doing “No references have been relied on, the claims having been rejected for the reason that they were too broad and were without adequate support in the description.” With respect to the primary point here in issue the board stated: “It appears also to be appellant’s view that the omitted details from the example on page 7 [of appellant’s specification] may be readily supplied by anyone skilled in the art. It is said for example, that the heating temperature must necessarily be something above the room temperature and below the boiling point of the aqueous medium. This is of course a very wide range of temperatures and it appears to us that a compliance with the requirements of Sect. 4888, R.S. would require a definite statement of the temperature as well as other essential conditions for carrying out what the inventor believes to be the best mode of accomplishing his invention.”
Appellant petitioned for rehearing and reconsideration of the decision of the board, contending that no person skilled in the art, with appellant’s disclosure before him, *618would have the slightest difficulty in selecting a suitable temperature for carrying out the claimed reaction, and that temperatures between about 135° and 220°, Fahrenheit, are typical temperatures employed for such a purpose by any person engaged as a j our-neyman in the field of chemical compounds characterized by the presence of polysulfide linkages.
In support of the petition for reconsideration appellant submitted proof in the form of an affidavit by Franklin O. Davis to show that the art was familiar with the appropriate temperature to be used and that this temperature was demonstrated by a number of prior art patents listed in the affidavit. The contents of the affidavit was summarized for the board as follows:
As appears from that affidavit and the prior art identified therein alkaline poly-sulfides have been extensively employed in polymer-forming reactions and in such reactions solutions of alkaline polysulfides have been heated with other reactants at temperatures between about 135 °F. and 220°F.
Appellant further contended that the position of the examiner and the board was completely refuted by the facts detailed in the affidavit by Davis, who at the time was assistant manager of the Research and Development Department of the Thickol Corporation. With reference to him and his unquestioned standing in the art, appellant stated before the. board: “He is a man skilled in the art at the time of applicant’s application, he selected a temperature of 185° F., without any experimentation for carrying out the reaction described by applicant in the example on page 7 of applicant’s specification and the said Franklin O. Davis had no difficulty in successfully following applicant’s instructions.”
The petition requesting reconsideration was granted but denied on reconsideration with respect to making any change in the board’s original decision. On the primary point in issue, the board stated: “We are still of the opinion that the present disclosure does no comply with the requirements of the statute as to proper support for the claimed subject matter.”
Under the general provisions of the patent laws governing the application for and the issue of patents,3 and under certain rules of practice prescribed by the Commissioner of Patents for the conduct of proceedings in the Patent Office,4 noncompliance by an inventor with the provisions of R.S. § 4888 with respect to an adequate description is a question of fact5 upon which the Primary Examiner, and not the applicant, has the burden of proof.6
An essential condition not implied by the familiar knowledge of one skilled in the art may not be omitted from the description required by R.S. § 4888 and in his description an inventor must do something more than give cues for future experiments.7 However, to condemn a disclosure for insufficiency, it is by no means enough to show that even a person skilled in the art may find it necessary to make several tests or trials before he attains the- desired result.8 *619Moreover, invention may be involved in a disclosure which provides that the respective steps of the process defined by the appealed claims may be carried out at the temperature most effective to obtain the desired results.9
The Board of Appeals nowise controverted appellant’s contention, and the authorities cited in his petition for reconsideration, that under the well settled doctrine of this court as disclosed by those authorities the burden of proof rested upon the tribunals of the Patent Office, and not upon the applicant, to show that the appealed claims were too broad and the disclosure of the specification was insufficient; and that this burden of proof is not sustained by assertions to that effect unaccompanied by a factual recital of support. Mention of the point has been likewise omitted from the brief submitted on behalf of the Solicitor for the Patent Office.
There can be no question, however, of the validity and predominance of the rule that the burden of proof is upon the Primary Examiner, and not the applicant, to show that a claim presented for allowance covers an inoperative species, or that it is too broad, or that the disclosure in the specification is inadequate or incomplete. Those three points, as here, are often closely related.
Appellant states in his brief, and the point is nowhere disputed, that the art was already familiar with condensation products of the acid-glycol reaction, as disclosed by the British patent to Groves hereinbefore described. Appellant also urges that “Quite obviously there are situations where it is necessary to specify a precise temperature, and others, like the present, where the reaction will occur (though at different speeds) at any common temperature.” Appellant further contends with persistent vigor that: “The Patent Office has given neither applicant nor this Court any opportunity to understand the reasons for its objections to the disclosure, or what materials, if any, it believes to be inoperative, what materials or reactions, if any, it believes would give undesirable results, why the materials or conditions given are not representative or sufficiently informative, or what expected degree of heating could be so undesirable as to render it necessary that a particular degree be specified; and such a situation will prevail more and more in cases such as this if the rule that the burden of proof is on the Patent Office is weakened. * * * ”
There is no doubt whatever that the court may not take judicial notice of any feature defined in an issued patent which is no part of the record before the court and which is not a matter of common knowledge.
The Board of Appeals in the instant case, with respect to the affidavit which was submitted with the petition for rehearing, held that “Under the provision of Rule 138, we must refuse to accept the affidavit or to remand the case to the Primary Examiner for reconsideration in view of such affidavit.” The soliciter in his brief likewise contends that “under the established rule of this Court, the affidavit is not properly before the Court for consideration,” citing In re Ayers and In re Ripper.10
Those two decisions were rendered in support of the proper construction and application of old Rule 138 of the Rules of Practice in the Patent Office. Were that the prevailing rule in the Patent Office when the decision in the instant case was rendered by the Board of Appeals, the rule would have governed the situation presented by the record. It is noted, however, that the decision of the board on the point in question was rendered March 10, 1949, and that on the previous March 1, 1949, Lawrence C. Kingsland, then Commissioner of Patents, had adopted and promulgated, effective as of that date, new rules governing the practice and procedure in the Patent Office whereby old Rule 138 was revised and supplanted by new Rule 195, which reads: “195. Affidavits after appeal. Affidavits or exhibits submitted after the case has been appealed will not be admitted without a showing of good and sufficient reasons *620why they were not earlier presented.” [Rule 138.]
The rejection of claims on the ground of insufficiency of the disclosure in the application is not merely a matter of practice in the Patent Office but one which is plainly within the supervisory jurisdiction of this court.11 And while it is beyond the spirit of the law for the court to order the issuance of a patent which, upon attack, would be declared invalid because of the insufficiency of its disclosure, or because of its infringement of the prior art,12 nevertheless where the insufficiency has not been clearly shown, or where, as here, the art relied upon to invalidate the claims has been considered and rejected by the Patent Office, the presumption of validity, while not conclusive, is greatly fortified.13 However, as Chief Judge Garrett correctly pointed out in a recent case:14 “Our primary concern, in cases such as this, is not what might happen in an infringement proceeding if the appealed claims should be allowed, but with the fundamental question of whether their allowance is proper.”
Despite appellant’s failure in his specification or claims to name the specific degree of temperature to which the involved mixture must be heated to effect the reaction, it is obvious that the exact nature of such temperature is not a characteristic essential to novelty. The appealed claims are not subject, therefore, to the criticism that the language of the claims is indefinite “at the exact point of novelty” as was the language of the claims rejected in General Electric Co. v. Wabash Appliance Corp., 304 U.S. 364, 371, 58 S.Ct. 899, 903, 82 L.Ed. 1402. Nor is there any tangible reason of record why the appealed claims should be rejected on the ground of undue breadth.
For the reasons stated, the decision of the Board of Appeals should be reversed.15
. In re Hutchison, 104 F.2d 829, 26 C.C.P.A.,Patents, 1670.
. Ex parte Lilienfeld, 44 U.S.P.Q. 174.
. R.S. §§ 4888, 4893, 4903, 35 U.S.O.A. §§ 33, 36, 51.
. Rules of Practice in the United States Patent Office 65, 66, 135, new Rules 104, 106, 107, 111, 112, 193, effective March. 1, 1949, 35 U.S.C.A.Appendix. See also In re Stover, 146 F.2d 299, 32 C.C.P.A.,Patents, 823, 825.
. A. B. Diek Co. v. Barnett, 2 Cir., 288 F. 799.
. In re Vickers, 141 F.2d 522, 31 C.C.P.A.,Patents, 985; In re Hunter, 166 F.2d 189, 35 C.C.P.A.,Patents, 931; In re Whitfield, 174 F.2d 137, 36 C.C.P.A.,Patents, 1023; Ex parte Edmond Riszdorfer, 34 U.S.P.Q. 338; Ex parte Jacobson, 39 U.S.P.Q. 326; Ex parte Johnson, 40 U.S.P.Q. 576; Ex parte Lilienfeld, 44 U.S.P.Q. 174; Ex. parte Schroy, 58 U.S.P.Q. 621, 622; Ex parte Amende and Ender, 72 U.S.P.Q.. 394; Ex parte Adams, 77 U.S.P.Q. 482.
. Standard Brands v. National Grain Yeast Corp., 308 U.S. 34, 38, 60 S.Ct. 27, 84 L.Ed. 17; In re Beach, 152 F.2d 981, 33 C.C.P.A.,Patents, 815; H. Ward Leonard, Inc., v. Maxwell Motor Sales Corp., 2 Cir., 252 F. 584, 588.
. Eibel Process Co. v. Minnesota & Ontario Paper Co., 261 U.S. 45, 65, 43 S.Ct. 322, 67 L.Ed. 523; Lever Bros. Co. v. Procter & Gamble Mfg. Co., 4 Cir., 139 F.2d 633; A. B. Dick Co. v. Barnett, 2 Cir., 288 F. 799.
. In re Haney, 158 F.2d 296, 34 C.C.P.A., Patents, 767.
. In re Ayers, 154 F.2d 182, 33 C.C.P.A., Patents, 874; In re Ripper, 171 F.2d 297, 36 C.C.P.A.,Patents, 743.
. In re Stauber, 45 F.2d 661, 18 C.C.P.A., Patents, 774.
. In re Kuhn, 150 F.2d 145, 32 C.C.P.A.,Patents, 1110.
. Hunt v. Armour & Co., 7 Cir., 185 F.2d 722, 726.
. In re Muskat, 187 F.2d 626, 38 C.C.P.A.,Patents, -.
. Since writing tbe dissenting opinion hereinbefore set forth, I have discovered that the United States Circuit Court of Appeals for the District of Columbia Circuit has also squarely held, in accordance with the provisions of the patent laws and the rules of practice of the Patent Office, not only that the Primary Examiner and likewise the Board of Appeals, in passing upon an applicant’s claims for a patent, are required to state the reasons for their opinions on the question of patentability, but also that no responsibility whatever rests upon the applicant to request that the required reasons be so stated by those tribunals. International Standard Electric Corp. v. Kingsland, 83 U.S.App.D.C. 355, 169 F.2d 890.