This appeal is from the decision of the Patent Office Board of Appeals affirming the rejection of all claims of appellants’ application for patent, serial No. 259,-014, filed November 29, 1951, on “14-Hydroxy Androstenes.”
The original opinions in this case were handed down on June 24, 1958. The court’s decision reversed the rejection of the claims. After extensions of time granted on motion and stipulations, the Patent Office filed a Petition for Rehearing on August 25, 1958 and appellants’ objections thereto were filed September 29, 1958. We granted the petition on April 17, 1959. Appellants and the Patent Office filed additional briefs on October 19 and 20, 1959. Amicus curiae briefs were received during September from the American Patent Law Association and the Connecticut Patent Law Association and the Philadelphia Patent Law Association filed a “Statement” saying that it approved and adopted the position taken by the American Patent Law Association in its amicus brief. All *175amici supported appellants’ position and urged us to adhere to our decision. Re-argument was heard November 2, 1959, counsel for appellants, the American and Connecticut associations, and the Patent Office participating.
In accordance with our usual practice, our former opinions have been withheld from formal publication. They are hereby withdrawn. The following is the opinion of the court. While we have revised our first opinion our former decisions are unchanged.
Introduction
The legal issue in this case has evinced the changeability of a chameleon, exhibiting sometimes subtle and sometimes complete changes of color. In introducing the subject we can, however, say with complete certainty that the ultimate question is whether the disclosure "of appellants’ application is sufficient to support a patent. There is no rejection on prior art, no question of novelty or un-obviousness or that the invention is in a category of subject matter on which patents can be granted. Utility seems to be involved but the precise Patent Office position on this point is still obscure.
Appellants have disclosed a group of novel compounds and how to make them. They have also said certain things about what can be done with them and how to do it. Appellants and the amici contend that this disclosure is sufficient to support a patent and the Patent Office says it is not. Who is right depends on what the specification says either about the utility of the invention or how to use the novel compounds, or both, and what the law is on these matters.
The law, at least in its statutory form, can be most simply stated. In Title 35 of the United States Code, section 101 reads, in pertinent part, as follows:
“Whoever invents or discovers any new and useful * * * composition of matter * * * may obtain a patent therefor, subject to the conditions and requirements of this title.”
This limits the grant of patents to “useful” inventions and this is the “utility” requirement of the statute. We must also consider section 112 which says [emphasis ours]:
“The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or carrying out his invention.”
In section 112 there are the “how to use” and the “best mode” requirements about which much of the argument in this case revolves.
The Disclosure
The claims on appeal are directed to new steroid compounds, claims 1 and 10 being typical and reading:
“1. A C-19 14 a -hydroxy-an-drostene wherein the double bond is attached to the carbon atom 5.
“10. 14 a-hydroxy-4-androstene-3, 17-dione.”
Claim 10 was copied by appellants from Murray et al. patent No. 2,662,089 (issued on an application filed after appellants filed) in order to provoke an interference. Appellants’ specification contained, when filed, the following statements about the use of the claimed compounds [emphasis ours]:
“The cardiac glycosides, such as digitoxigenin and the like, comprise steroids which contain an OH-group in the 14-position. Important physiological properties are attributed to these steroids. However, synthetically produced C-19 H-hydroxy-androstenes wherein the double bond is attached to carbon atom 5 have not heretofore been known.
“A primary object of the present invention is the embodiment of such synthetically-produced compounds, *176corresponding to formula I supra.1 These new compounds are valuable intermediates in the preparation of steroids wherein a hydroxyl group is present in the 14-position, and of steroids containing a 14,15-double bond, and -of steroids the synthesis of which requires such groupings.
* * * * * * “Conversion of the androstene compounds to produce analogous saturated 14-hydroxy steroids is effected by hydrogenating the A 5-double bond, for example by catalytic methods.”
The specification also teaches that the acyloxy groups in the 3- and 11- positions of appellants’ compounds can be hydrolyzed to the corresponding 3-hydroxy groups and the latter oxidized to keto groups to produce the corresponding ke-tone compounds. It also teaches how the 17-keto group can be reduced to a hydroxyl group with the aid of an agent such as catalytic hydrogen, sodium boro-hydride, lithium aluminum hydride and the like, following these statements with illustrative reaction schemes setting forth the conversions by means of graphic formulae.
The Rejection
The board described the rejection thus: “Claims 1 through 7 and 10 have been rejected as lacking utility.” [Emphasis ours.] This is the rejection it affirmed. The examiner’s final rejection of July 26, 1954, which the board .had under review, said [emphasis ours]:
“Claims 1 to 7 and 10 are finally rejected for lack of utility for the reasons fully explained in the last Office letter. * * *
“ * * • * in view of the fatally defective nature of the present application, applicants are not entitled to a patent * *
The examiner’s Answer, on the appeal to.the board, after stating again that the claims were under rejection “as lacking in utility,” also said, inter alia,
“The applicants fail to show how these intermediates can be converted to products having known useful properties. The■ mere allegation that they are useful for conversion is not sufficient. * * * there is no justification for assuming that a conversion product of the claimed compound will be useful. * * * the disclosure is fatally defective with respect to [the] utility requirement of 35 USC [§] 112 * * [Emphasis ours.]
Since the board affirmed the examiner’s rejection, that, of course, is the ground of rejection which is before us for consideration. In re Scharwath, 164 F.2d 609, 35 CCPA 763.
The essence of the board’s reasoning in affirming the foregoing rejection is contained in the following excerpts from its first opinion:
“There is no assertion in appellants’ specification that they are able to synthesize an active digitalis gly-coside from their intermediate, nor any other specific physiological active steroid having a hydroxyl group in the 14-position or with a 14,15-double bond. [Emphasis ours.] ******
“ * * * there is no evidence before us that * * * appellants ever produced a useful steroid from their * * * intermediates. [Emphasis ours.]. ******
“35 U.S.C. [§] 112 requires an applicant to fully describe how to make and use- the invention and to set forth the best mode contemplated of carrying it out. Clearly appellants have failed to do that in this case because they haye not shown how their intermediate may be used to prepare a single useful steroid. We are unable to conclude that a method for doing this would be ob*177vious to one skilled in the art. [Board’s emphasis.]
“There are of course cases where no utility need be disclosed because it is either obvious or well known. However an incomplete disclosure, in a case (as herein) where utility is necessary to a full disclosure of the invention, is no better than one totally lacking it because both fail to comply with 35 U.S.C. [§] 112.” [Emphasis ours.]
The board, as did the examiner, cited the 1950 decision of this court in In re Bremner et al., 182 F.2d 216, 37 CCPA 1032 and seemed to regard that case as the controlling authority supporting its point of view. We shall point out later why the Bremner case fails to support the rejection.
The Issue
It will be seen from the foregoing that the rejection was variously predicated on lack of utility, failure to show utility, failure to allege sufficient utility, failure to comply with the “utility requirement of 35 USC [§] 112” and failure to disclose how to use the claimed compounds. Out of this congeries of explanations as to why the specification was allegedly “fatally defective” the Patent Office solicitor distilled the statement in his original appeal brief that
“ - * * it is clear that what is meant is that the claims are based upon a specification which fails to contain a written description of the manner of using the invention, as required by Section 112 of Title 35 U.S.C.” [Emphasis ours.]
That is clear, standing by itself, but the brief then proceeds to argue that the real defect was that “applicants fail to show how these intermediates can be converted to products having known useful properties,” for which reason they were not shown by the disclosure to be useful. It argues that it is on the utility of the compounds into which appellants’ compounds were to be converted that the case hinges “since a compound which acts as an intermediate for the production of another compound having no utility can hardly be said to be useful in the sense of the law.” [Emphasis ours.] Thus does the brief inextricably tie up the question of disclosure of how to use under section 112 with the issue of utility under section 101.
The Patent Office petition for rehearing charged us with an extrajudicial excursion, in our original opinion, into the meaning, and bearing on the issues, of section 101 and with rendering an advisory opinion thereon which we should withdraw. We considered section 101 because we were of the opinion — after an intensive, not to say frustrating, effort to determine on what ground the claims were rejected — that the examiner’s rejections and the board’s reasoning involved a scrambling of the separate statutory requirements that an invention must be useful to be patentable, and that an application, to comply with the law, must adequately teach those skilled in the art how to make and use the invention. We are still of that opinion and we therefore as requested in the Connecticut amicus brief, retain in our opinion an expression of our views as to the bearing on the issues of both sections 101 and 112. As the American amicus brief points out, the Patent Office has taken the position that appellants have not complied with section 112, but it has not shown why this is so except by objection to the kind of utility disclosed, which presents an issue under section 101 rather than under section 112.
In its brief on the rehearing the Patent Office again stated the issue to be solely whether the requirements of section 112 have been complied with, but its interpretation of this issue in the brief as a whole and in oral argument is that section 112 has not been complied with because the specification does not show that a patentable invention has béen made for the reason that the invention described is not useful under section 101, or at least that such use as is disclosed is insufficient under section 101. Mention of section 101 has been avoided but this construction is inescapable.
*178The issue here cannot, therefore, be restricted to a consideration of the disclosure of how to use, under section 112, and necessarily requires a consideration of the requirement of section 101 that an invention, to be patentable, must be “useful.” Section 112, as we view the matter, does not deal with “utility,” in the sense in which that term is used in patent law to define a prerequisite to patentability.
Utility
The grand objective of the patent system, as stated in the Constitution, is to promote the progress of the useful arts. Presumably for this reason, our patent statutes, from the very beginning in 1790 to the latest act of 1952, have made it a prerequisite to patentability that the invention be new and useful. However, it has never been a requirement for patentability that there must be any particular degree of utility. To cite a very early text, Curtis On Patents (1849) says, in section 16,
“The word ‘useful’ is not supposed to be used, for the purpose of establishing general utility as the test of a sufficiency of invention to support a patent. It had been held, upon the use of the same word in the old patent act of 1793, that it was used merely in contradistinction to what is frivolous or mischievous to society. This term was held to be satisfied, if the alleged invention was capable of use, and was not injurious to the well-being, good policy or sound morals of society. [Cases cited: Lowell v. Lewis, [Fed. Cas.No.8,568], 1 Mas. 186; Bedford v. Hunt, [Fed.Cas.No.1,217] Ibid. 303; Knease [Kneass] v. Schuylkill Bank, [Fed.Cas.No.7,875] 4 Wash.[C.C.] 9, 12.]” [Emphasis ours.]
Again in section 28, after repeating the substance of the above, he says,
“ * * * it follows that every invention, for which a patent is claimed, must be, to a certain extent, beneficial to the community; it must be capable of use, for some beneficial purpose; but when this is the case, the degree of utility, whether larger or smaller, is not a subject for consideration, in determining whether the invention will support a patent. But it is obvious that the capability of use for some beneficial purpose is a material element in determining whether there is a sufficiency of invention to support a patent; the force of the word ‘useful,’ introduced into the statute in connection with the epithet ‘new,’ being to determine whether the subject-matter, upon the whole, is capable of use, for a purpose from which any advantage can be derived to the public. General rules will not decide this question in particular cases, but the circumstances of each case must be carefully examined, under the light of the principles on which general rules are founded.” [Emphasis ours.]
See also Curtis on Patents, 4th Ed., (1873) § 106, page 111, enlarging on this theme.
Looking at an even earlier text, written contemporaneously with the patent act of 1836, The Law of Patents For Inventions by Phillips (1837) in Chapt. VII, Subjects of Patents, Sec. 14, Usefulness (10 pages), the following, quoting a classic statement of Mr. Justice Story,2 appears (p. 139):
“All that the law requires is, that the invention should not be frivolous, *179or injurious to the well-being, good policy, or sound morals of society. The word useful, therefore is incorporated into the act in contradistinction to mischievous, or immoral. For instance, a new invention to poison people, or to promote debauchery, or to facilitate private assassination, is not a patentable invention. But if the invention steers wide of these objections, whether it be more or less useful is a circumstance very material to the interest of the patentee, but of no importance to the public. If it be not extensively useful it will silently sink into contempt and disregard. (From Lowell v. Lewis, 1 Mason 182.) [Fed.Cas.No.8568]”
This passage was quoted with approval by the Circuit Court of Appeals, Third Circuit, in 1947 in Cusano v. Kotler, 159 F.2d 159.
Again at page 142, with footnote references to texts and cases, the above author, Phillips, says:
“The requisite of usefulness has been sometimes contrasted with frivolousness, and the multiplicity of patents for trivial subjects has been occasionally deprecated by judges. An invention may be slight and trivial as being so obvious and apparent that it cannot be considered a discovery, or it may be trivial or frivolous in respect to its effect upon industry and production. A defect in the first sense renders the patent void as being for a subject that is not an invention. But an invention of a very slender character in the latter sense is still the subject of a patent, since it is not the province of the court to go into the question of the extent or degree of usefulness. It is enough that the invention is useful; how useful it may be is immaterial.” [Emphasis ours.]
In EL C. Merwin’s text, Patentability of Inventions (1883), p. 75 the author states:
“As to the term ‘useful’, the courts have construed the condition expressed by it so liberally that it almost never serves to defeat a patent. The following rules are clearly established: 1. Anything is useful which is not entirely frivolous or worthless, and not detrimental to the well-being, or injurious to the morality of the public, or of a character to mislead the public to its disadvantage. 2. The subject of a patent need not be the best or most useful of its kind. It is necessary only that it should be useful in some degree. 3. It need not possess all the usefulness, or the degree of usefulness, claimed for it in the patent. 4. In a suit for infringement, if the defendants are proved to use the invention described in the patent sued on, they are estopped to deny its utility.” [Emphasis ours.]
The classic text, Robinson on Patents (1890), says:
§ SU1. Degree of Utility Immaterial.
“When actual utility exists, its degree is unimportant. However slight the advantage which the public have received from the inventor, it offers a sufficient reason for his compensation; and as he could withhold this slight advantage if he chose, his surrender of it to the public places him on the same plane of merit with every other inventor. Nor is it necessary that this advantage, whether great or small, should flow directly from his art or instrument, considered by itself. For though it is a mere improvement upon pre-existing arts or instruments, or is incapable of serving any purpose except as an integral part or element of some different invention, or embodies an idea or means whose highest value can be realized only by advancing it to a more perfect state of development, it still has an inherent usefulness which satisfies this requirement of the law.” [Emphasis ours.)
*180 In a somewhat later text published at the turn of the century, Walker on Patents (5th Ed., 1904), the chapter on “Utility” occupies but six and a half pages (pp. 97-103). The concepts set forth are simple. “To possess utility, a thing or a process must be capable of producing a result, and that result must be a good result.” “Utility is absent from all processes and devices which cannot be used to perform their specified functions, and patents for such subjects are therefore void.” “Whatever is beautiful is useful, because beauty gives pleasure, and pleasure is a kind of happiness, and happiness is a kind of utility.” Hence, a thing having no function except to decorate is useful, Magic Ruffle Co. v. Douglas, 1863, Fed.Cas.No.8,948, 2 Fish.Pat.Cas. 330. On the contrary, “Utility is negatived if the function performed by an invention is injurious to the morals, the health, or the good order of society.” “A patent is prima facie evidence of utility * *
Rogers on Patents (1914), Vol. 1, page 9, says:
“ * * * utility in its broadest sense approaches a presumption more nearly than any other point recited in the statute and is seldom questioned by the courts or the Patent Office, except in cases of perpetual motion, or in such cases, for example, as a spark arrester which works so vigorously as to stop the locomotive, or some visionary, obviously impracticable, scheme.”
As a subsequently arising example of the last- mentioned type of invention one might cite the decision of this court in In re Oberweger, 115 F.2d 826, 828, 28 CCPA 749, wherein an invention consisting of various admixtures of such things as-bone marrow, aromatic oils and alcohol was held lacking in utility for the specified purpose of growing hair. The court referred to the fact that the “concoction * * * belongs to a class of compositions which from common knowledge has long been the subject matter of much humbuggery and fraud.” See also In re Perrigo, 48 F.2d 965, 18 CCPA 1323.
In National Slug Rejectors, Inc. v. A. B. T. Mfg. Corporation, 7 Cir., 164 F.2d 333, 335, Judge Evans said, “It is not the extent of the utility that governs, but the existence of some utility,” citing 40 Amer.Jurisprudence, “Patents,” Sec. 43, p. 546. Quite recently, citing a number of authorities, the District Court for the Southern District of New York held that “Absent proof of total incapacity the defense of non-operativeness or non-utility is not available.” Technical Tape Corp. v. Minnesota Mining & Mfg. Co., 143 F.Supp. 429, 438.
Now let us consider whether applicants’ new compounds, the claimed C-19 14-hydroxy-androstenes, are “useful” by the legal standards discussed above, according to the information which is given to us in the specification. We are told thereby that these are new androstenes, of a kind never before made (and novelty has not been questioned), that they are of a type which steroid-chemists can use in well-known reactions to produce steroids of a class at least some members of which are known to have useful therapeutic properties. Appellants’ point is that new “building blocks” of value to the researcher have been supplied which have utility as intermediates in the search for cheaper and shorter routes to the synthesis of steroids having therapeutic or similar ultimate utility.
The Patent Office position seems to have been that there must be a presently existing “practical” usefulness to some undefined class of persons. We have never received a clear answer to the question “Useful to whom and for what?” Surely a new group of steroid intermediates is useful to chemists doing research on steriods, and in a “practical” sense too. Such intermediates are “useful” under section 101. They are often actually placed on the market tie-fore much, if anything, is known.as to what they are “good” for, other than experimentation and the making of other *181compounds in the important field of research. Refusal to protect them at this stage would inhibit their wide dissemination, together with the knowledge of them which a patent disclosure conveys, which disclosure the potential protection •encourages. This would tend to retard rather than promote progress.
The new androstenes, being useful to ■research chemists for the purposes disclosed by appellants, are clearly useful to .society and their invention contributes to the progress of an art which is of great ■potential usefulness to mankind. They .are new steroids which in known ways can be made into other steroids, thus furthering the development of this useful art.
We conclude that the claimed compounds are “useful” within the meaning •of section 101 and that there is a disclosure of the utility in the specification. We turn now to the question of whether the disclosure of “the manner * * * •of * * * using” is sufficient to comply with section 112.
Requirements of Specification
Of equal antiquity with the utility requirement of the statute is that for a specification which, as provided by .section 2 of the act of 1790, 1 Stat. 110, was required to be of such particularity .as would “enable a workman or other person skilled in the art * * * to ■make, construct, or use” the invention. No real alteration has been made in this, law through the years or in the fundamental reasons for requiring such a specification, which are two. Quoting again from Phillips, The Law of Patents (p. :233):
“There are two objects in view in making a specification. As the law grants the patentee a monopoly, and not only awards damages, but inflicts a penalty for violation of the ■exclusive privilege, it very equitably requires that the invention shall be .so described in the specification, that •every person may, by examining it, know what the patentee claims, and <be able to distinguish what may be an infringement. The other object of the specification is to give the public the advantage of the invention after the expiration of the patent. The consideration of the patent being the advantage to be derived to the public-after its expiration, it is necessary, in order that this advantage may be realized, that the - invention shall so be described in- the specification, that one acquainted with the art or manufacture, to which it relates, or with which it is most nearly connected, may not only understand the invention, but be able, by following the directions given in the specification, with the assistance of the drawings, to construct the machine or perform the process which is the subject of the patent. These two objects of the specification are the foundation of the rules and decisions in regard to it.” [Emphasis ours.]
Reáding the first paragraph of section 112 of the Patent Act of 1952, quoted at the beginning of this opinion, will show that in more than a century nothing of substance has been changed in this portion of the statute. We add; to Phillips’ explanation of its purpose, however, that a further public advantage from' the specification is the addition it makes to technical literature immediately upon issuance of the patent, without waiting for its expiration.
The board said that “clearly” appellants have not complied with the requirement that they “fully describe how to make and use the invention and * * * set forth the best mode contemplated of carrying it out.” It is not so clear to us that appellants, have failed to comply.
The descriptions in patents are not addressed to the public generally, to lawyers or to judges, but,’as section 112 says, to those skilled in thé art to which the-invention pertains or with which it is most nearly connected. The sufficiency of a specification must be tested in the light of this fact and judged by what it conveys to those who are ¿killed in the-art. The judge’s task is’to decide *182whether from the disclosure the man skilled in the art can make the invention and use it. If he can, this part of the statute is complied with, subject to the one further requirement that the inventor describe the best mode contemplated by him of carrying out his invention.
Let us now examine what appellants have disclosed in their specification about their new compounds and how to use them. First, they have fully described their compounds and how to make them. No question has been raised as to this. Secondly, as to the “best mode * * * of carrying out” their invention, their invention is the new compounds, not something to be done with them. The only apparent way in which it can be “carried out,” it seems to us, is to make the compounds and no question has been raised but that the best way known to the appellants of doing this has been disclosed. Finally, we come to the description of how to use the invention, i. e. the C-19 14-OH-androstenes claimed. Appellants have said to those skilled in the art: Use them as intermediates to make other steroids having analogous structures; you can do this by hydrogenating the delta-5 double bonds by catalytic methods which you already know about. Similarly, with respect to other reactions, to which we referred above, other hydrolysis and oxidation procedures were suggested and we have no doubt that those skilled in the steroid art would know of many other reactions in which they could use these intermediates in the course of their research. Are appellants entitled to a patent on this disclosure? We think they are. We are unable to see any fatal defect with respect to the disclosure of hern to use the invention.
The Patent Office brief argues that granting this patent would not be a carrying out of the constitutional objective of promoting progress of the useful arts. With this contention we wholly disagree. How does the patent system function to promote progress? It is not like a system of military awards in which medals are given out by the people to their heroes as expressions of gratitude for their exceptional services. While the element of reward is one factor in the patent system, it is probably the least important. The patent system is an incentive system calculated to do two things, principally. First, it stimulates work, research, development, invention, and discovery by holding out the prospect of profit. Second, in exchange for and as a condition of the patent protection, it secures a full disclosure of the invention. Promotion of the useful arts takes place through the combination of these two factors, the doing of the work and the disclosure of the results thereof. In the very nature of things, progress is made as the result of both the big and the little contributions, mostly the latter. We get a telephone or a triode — in modern jargon a “major scientific breakthrough” —only at rare intervals. The seemingly little advances are the bread and butter of progress and sometimes turn out to be of much greater importance than at first thought. The biggest contribution the patent system makes to progress is to induce a steady flow of contributions and to secure their continuous disclosure.
As a corollary, there is the matter of private publication of the results of research which in turn fertilizes and assists further research. Accepting, argu-endo, the statement in appellants’ brief that a description of their invention was published some years ago in the belief that their patent application was legally adequate (and it was, by prior standards of the Patent Office), clearly self-interest would have dictated a withholding of that publication if the board’s decision is correct; for a satisfactory application would have had to await the day when some use of the new androstenes other than that disclosed had been discovered. The disclosure of these new compounds and how to make them would not have been made, either by publication or patent application. They would have been kept secret and would not have become part of the stream of progress. We think an affirmance of the rejection here would *183tend to defeat the constitutional objective.
What the Patent Office is really trying to insist on here has nothing to do with the “how to use” provision of section 112. It is demanding some different, or greater, or more commercial or more mundane use than the one disclosed. Just what kind of use, we have been unable to discover although it is apparent that the Patent Office would have been satisfied if the new compounds, or other steroids made therefrom, had possessed therapeutic activity.
Essentially the reason given by the board for its decision affirming the rejection seems to be that appellants have not shown the production from their new androstenes of a single physiologically active steroid. While the board itself has rendered some decisions tending to support its view that this is necessary,3 notably Ex parte Tolkmith, 102 USPQ 464 (1954), and an unpublished decision discussed in the article it cited entitled “The Utility Requirement in Chemical Patent Applications,” 38 J.P.O.S. 282 (1956), the only higher authority cited which is in point is the opinion of this court in the Bremner case, supra.
The Bremner Case and What a Specification Must Say About Utility and How to Use
The Bremner case, 182 F.2d 216, 217, 37 CCPA 1032, decided by this court in 1950, sustained a rejection on the ground that the specification failed to comply with R.S. 4888 (35 U.S.C., 1946 ed., 33, the predecessor statute to 35 U.S.C. § 112). While eschewing any “hard and fast” rule on disclosure of “utility” in a specification, the court said it felt certain that the law required “an assertion of utility and an indication of the use or uses intended.” The case has been cited as authority for this proposition ever since.4 The board and the examiner have relied on it to support the rejection in the present case.
It is clear to us that the above “rule” of the Bremner case has been fully met in appellants’ application. They have asserted that their new steroid compounds are useful and they have indicated that the intended use is in the field of steriod chemistry wherein they have utility as intermediates in synthesizing other steroid compounds. Nothing in the Bremner case requires more. The Brem-ner case requires that the specification must “indicate” the use or uses of the invention intended by the applicant. The court held that the Bremner et al. application, in spite of its disclosure of “resins” and melting points, contained nothing indicating a úse, and the rejection was sustained. Now, it was strenuously argued that anyone skilled in the art would know what to do with the “resins” disclosed, that all new chemical compounds have obvious utility as intermediates, citing Ex parte Watt, 63 USPQ 163, 165, and a Lewers article, 4 J.P.O.S. 530, 542, and hence utility may be assumed as to all new compounds. The court’s answer was that the applicants’ specification has to indicate the intended use or uses, which is a requirement distinct from the mere possession of “utility.” *184We are not disposed to alter this requirement, which has now been the case law for a decade. We do believe, however, that its rationale needs elucidation.
Much confused thinking on this matter has resulted from a failure to separate the requirement of section 101 that an invention be useful from the section 112 requirement that a specification shall so explain “the manner and process of * * using” the invention as to “enable any person skilled in the art * * * to * * * use the same.” Possibly the difficulty of applying the language of section 112 to diverse fact situations contributes to the confusion, for that language is not tailored to fit all of the kinds of inventions which may be patented under sections 100 and 101. For example, one cannot “make” a process and neither is it clear that “manner and process of * * * using” is apt with respect to a new “composition of matter.”5 Moreover, section 112, being the generalized provision that it is, leaves it to the Patent Office and the courts to make the final decision on whether the explanation of manner and process of use does in fact enable one skilled in the art to “make and use” the invention.
If we assume, arguendo, as was in fact argued by Bremner in his case, that all chemical compounds are inherently useful and so have the “utility” required by section 101, we are still left with the problem of compliance with section 112, which is not directed to the existence of usefulness but to what an inventor must disclose as the quid pro quo for patent protection.
The basic purpose of the requirement that the specification contain a written description of the invention is to put those skilled in the art in possession of sufficient knowledge “to enable” them to practice the invention. One cannot read the wording of section 112 without appreciating that strong language has been used for the purpose of compelling complete disclosure. There always exists, on the part of some people, a selfish desire to obtain patent protection without making a full disclosure, which the law, in the public interest, must guard against. Hence section 112 calls for description in “full, clear, concise, and exact terms” and the “best mode” requirement does not permit an inventor to disclose only what he knows to be his second-best embodiment, retaining the best for himself.
In keeping with the policy and spirit of this law, the rule of the Bremner case requires, as a minimum, that the inventor “indicate” a use for a new composition. As above stated, Nelson and Shabica did this, the use being as an intermediate in research on a specific class-of steroids. In adhering to the Bremner rule we wish to make it clear, however,, that the test is what the application as a whole communicates to one skilled in the art. In some cases an applicant may, merely by naming his new instrument or material, indicate what its use is, as, for example, by saying he has invented a “match,” “hammer,” “paint,” “adhesive,” or “detergent.” He may or may not have to go further in order to enable-others to use the invention, depending on its nature and on how much those of ordinary skill in the art know. In other-words, compliance with the law does not necessarily require specific recitations of use but may be inherent in description, or may result from disclosure of a sufficient number of properties to make a. use obvious; and where those of ordi*185nary skill in the art will know how to use, the applieant has a right to rely on such knowledge. If it will not be sufficient to enable them to use his invention, he must supply the know-how. As this court has often said before, each case must be judged on its own facts.
We believe our decision in this case to be consistent with the opposite result reached in the Bremner case because of the differences in the facts. Bremner disclosed eight polymers of dihydropyran and, since he said nothing whatever about use, he left it to the art to guess what to do with them on the basis of what he told about their properties. He said his solid polymers were “resins,” a word which, to a chemist, is broad enough to include a wide variety of diverse materials and which has no definite meaning. One of his products was a golden, highly viscous liquid soluble in benzene and the others were solids melting at temperatures from 60 °C. to above 200 °C. One was said to be “hard” and one was described as “colorless.” No other properties than these were disclosed.
The description of a liquid as golden, highly viscous and soluble in benzene is as applicable to engine oil and varnish as it is to Bremner’s liquid polymer. Bremner argued as to his solid products that they were inherently useful since any “resin” which is solid at room temperature and melts at a higher temperature can be molded by melting it and pouring it in a mold to solidify. But this amounted to no more than saying one can change the shape of the material, and applies to all thermoplastic materials including butter, roofing tar and candle-wax. It no more indicates or suggests a use than stating that big pieces of the material can be cut up into little pieces. Eventually, but too late, Bremner submitted an affidavit showing a use which could not possibly have been guessed from his disclosure, namely that “the polymers are useful as ingredients of polyvinyl chloride compositions,” more specifically as plasticizers.
Contrasting the disclosure of Bremner with that of the instant application, Bremner was completely silent as to what his polymers could be used for and did not disclose enough as to their properties to enable one even to make an intelligent guess as to a use. Bremner was the first to make polymers of dihydropyran. No one knew anything about them. Nelson and Shabica, on the other hand, were not silent. They included in their application an explicit statement that their compounds were for use in making specific steroids having certain structures, related to the structures of their own compounds, which they disclosed. They told what procedures could be used in using their compounds. Not only did they “indicate” a use, they explained it in detail and told how to carry it out in practice.
What has beclouded the issue in the present case is the nature of appellants’ use, which the Patent Office erroneously regarded as not meeting the statutory requirements on “utility.” With that issue out of the way, it is clear that they taught how to use their new compounds.
In holding, as we do, that appellants complied with section 112 in making a clear disclosure of use in steroid research, we do not mean to imply that applicants for patents on new compounds can now rest on an assumption that they are useful as intermediates and obtain patents without even suggesting what use may be made of them or how that use may be effected. We are not holding that all compounds are inherently useful as “intermediates.” We have reason to believe some are not, and it is a question of fact to be determined in each case. Assuming, however, that a given compound would be so useful, it would still be incumbent on the applicant to disclose what is to be made from it and how it would be done. What the Bremner rule requires is that an application shall make known to those skilled in the art something that can be done with a new compound and not, through silence, leave the matter entirely to speculation or independent investigation.
*186The Petrocarbon Case
The Patent Office urges upon us as an authoritative precedent the case of Petrocarbon Limited v. Watson, 101 U.S.App.D.C. 214, 247 F.2d 800, decided July 3, 1957, by the Court of Appeals, District of Columbia. The decision was by a divided court, Judge Burger dissenting with an opinion.
While we recognize the special competence of that court to deal with questions of patent law and accord substantial weight to its views as an appellate court of equal standing, we regretfully find ourselves in complete disagreement with the majority view on the question of patent law involved. While it is entitled to deference, it is not authoritatively binding on us. See Watson v. Allen, 103 U.S.App.D.C. 5, 254 F.2d 342. Since it involves a question of law on which that court as well as ours is frequently required to pass, we set forth with particularity our reasons for disagreement.
The Petrocarbon case, like the present case, involved the question whether a specification was fatally defective for failure to comply with section 112. The specification described new polymers, asserted to be useful, which deposited from vapors on cool surfaces in the form of a “film.” The film was described as having great thermal stability up to 270°C., was said not to be attacked by sulfuric acid at 150°C., and to be insoluble in, and not to swell visibly in, boiling solvents. Seven solvents of various types were named. The case turned on the meaning of the term “film” which was said to be well understood by those skilled in the art, though the court chose to find great ambiguity in it. The majority of the Court of Appeals sustained the District Court’s refusal to receive expert testimony and exhibits to show what “film” actually meant to those skilled in the art. This evidence, it seems to us, would have assisted the court in determining the fundamental issue of what the disclosure actually was. We agree with Judge Burger’s dissent on the ground that the evidence should have been received. Even without it, however, our own reading of the specification leads us to the conclusion that anyone skilled in the plastics art, knowing all of the chemical and physical properties given for the film, would know of many possible uses for the polymers and how to use them. The case differs from the Bremner case in the amount of information given about the new polymers which, in the Petrocarbon case, was sufficient to enable those skilled in the art to use the new materials and hence section 112 was complied with.
For the reasons above stated, we must respectfully decline to accept the Petro-carbon case as a precedent.
The Patent Office also relies on In re Perrigo, supra [48 F.2d 966], one of the few cases in this court on the subject of utility. The passage cited says,
“Neither the Patent Office tribunals nor the courts may properly grant patents upon a mere possibility that a device might do the things claimed for it and be useful.”
That statement has no applicability to the facts at bar because it was made in the context of an alleged invention, the description of which the court characterized as “not comprehensible,” either to it or to the tribunals of the Patent Office. The court had before it a device which was clearly incapable of being used for anything and was dealing with the rejection that it was “lacking in utility as a result of inoperativeness.” [Emphasis ours.] The above quotation continues,
“Neither the Constitution nor the statutes contemplate the granting of patents upon theories, nor giving a monopoly upon intellectual speculations embodied in devices incapable of scientific analysis.”
We are entirely in accord with that statement, but a specification fully describing how to make a group of new chemical compounds of a class containing highly useful members, what their structure is, what type of compounds they can be used to make, and how to go about doing *187so is far outside anything under consideration in the Perrigo case.
Reduction to Practice Cases
The Patent Office petition for rehearing asserted that our decision herein was inconsistent with a number of prior decisions in inter partes cases as to the proof of utility required to establish an actual reduction to practice. The cited cases in this court are: Muskat et al. v. Schmelkes, 140 F.2d 984, 31 CCPA 837; Saklatwalla v. Marburg, 172 F.2d 227, 36 CCPA 791; Kvalnes v. Wright, 183 F.2d 193, 37 CCPA 1147; Morway et al. v. Bondi, 203 F.2d 742, 40 CCPA 917; Reiners v. Mehltretter, 236 F.2d 418, 43 CCPA 1019; and Blicke v. Treves, 241 F.2d 718, 44 CCPA 753. Also cited were decisions of the Court of Appeals, D. C., in Knutson et al. v. Gallsworthy et al., 82 U.S.App.D.C. 304, 164 F.2d 497; and Larsen v. Marzall, 90 U.S.App.D.C. 260, 195 F.2d 200. We have carefully considered these cases and also Archer v. Papa, 265 F.2d 954, 46 CCPA 835; Kyrides v. Bruson, 102 F.2d 416, 26 CCPA 986; and Larson et al. v. Eicher, 49 F.2d 1029, 18 CCPA 1497, which were not cited but which are as pertinent, though less favorable to the Patent Office position.
We see no conflict or inconsistency as between our present decision and the decisions in those inter partes cases. All we are concerned with here is whether an application contains sufficient disclosure to comply with the law. In every interference it has already been determined, before the interference is declared, that the application of each party is in compliance with law. Insofar as this decision has an effect on the requirements of application disclosures, it will apply equally in inter partes and ex parte cases, as does all of the law on the subject; an application sufficient for one purpose is sufficient for all purposes, including the establishing of a constructive reduction to practice. It would not be proper in this ex parte case to make any pronouncement as to what is required by way of test to establish an actual reduction to practice in an inter partes case but it can be stated that so far as utility is concerned, there is but one standard to be applied, regardless of where or how the issue is raised. As to tests to establish utility, which may mean operativeness or suitability for an asserted use, an examination of the above cited cases will show that the requirements may vary all the way from no test at all to testing under actual service conditions. See Morway et al. v. Bondi, supra. Inter partes priority disputes involve policy considerations with which we are not concerned in an ex parte case and we cannot prejudge what will be required in future situations. All we say now is that the application before us adequately complies with the law.
The Patent Office point predicated on the above inter partes cases and strongly argued in the petition for rehearing appears to have been abandoned by failure to mention it in the solicitor’s rehearing brief. We have dealt with it, however, to make clear the fact that we have not overlooked it.
New Matter
One final point remains for disposal. During prosecution, in an effort to answer the examiner’s contention that the specification contained an inadequate disclosure of utility, appellants attempted to add a paragraph about which they stated in their “Remarks,”
“In the amendment filed December 10, 1952 it was pointed out how by known methods applicants’ compounds may be converted to known useful compounds shown in the Ru-zicka et al patent. These well-known and obvious steps have been incorporated in the specification.”
The examiner rejected the amendment as new matter only as to its last sentence but the board held the entire paragraph to be new matter.
Of course, if the application had been fatally defective, as alleged by the examiner, such a defect could not have been cured by an amendment the object of which was to put into the specification something required to be there when it *188was filed. The ñew matter rejection by the board on that theory was sound. However, we are reversing the finding that the specification was fatally defective.
We have considered the paragraph sought to be entered to augment the original disclosure of utility. It seems to us that it clearly goes beyond what is permitted by 35 U.S.C. § 132 and Patent Office Rule 118, 35 U.S.C.Appendix, which provides that “an addition to the original disclosure, cannot be added to the application.” The amendment appears to us to be an addition to the disclosure and the refusal to admit it will, therefore, be affirmed.
For the above-stated reasons, the decision of the board is reversed as to the rejection of claims but affirmed as to the admission of the amendment objected to as new matter.
Modified.
. Formula “I” is the general structural fori the specification. la of the claimed androstenes set forth in
. In his preface, Phillips, after referring to Chief Justice Marshall and some other judges, says: “But it is no injustice to the other eminent jurists of the country to say, that this department of the law has been more especially indebted to the learning and talents of Mr. Justice Story, the records of whose indefatigable research and luminous expositions, will be found in many parts of this volume.” Mr. Justice Story was on the U. S. Supreme Court 1811-45 and was also professor of law at Harvard 1829-45. He was the author of a famous series of Commentaries.
. The board has also entertained a contrary view in a situation having marked similarities to the present case but where the new compounds were remote from the pharmaceutical field. See Ex parte Ladd et al., 112 USP2 337, wherein a rejection on the ground the claims were “lacking in utility” was reversed by the hoard.
. The first law point discussed in the Bremner opinion was that a patent specification is required by law to assert “utility” and the factual finding was that it did not. We find on review of the record that the court was mistaken in saying there was no assertion of utility, for the opening statement of the Bremner et al. specification was that the invention was “new and useful.” Upon reflection, we are now of the opinion that a mere assertion of utility in a specification is a meaningless formality and no more required by law than an assertion of novelty. We think it only reasonable to infer from the fact of filing an application that the applicant asserts that the invention is new and useful, for unless it is both he has no right to a patent. 35 U.S.C. § 101.
. Text writers have glossed over the difficulties of applying this law to fact situations, as for example in Walker on Patents, Deller ed., Sec. 163, referring to RS..488S:
“The detailed description of the invention must be full enough, and clear enough, and concise enough, and exact .■.enough, toe enable any person skilled in the art or science" to which, it'appertains, or with which it is most nearly connected, to make and use the invention, if it is a machine or a manufacture, or to compound the invention, if it is a composition of matter, or to perform the invention, if it is a process.” [Emphasis ours.]
This was almost exactly the same in, Walker’s first edition, sec. 115.