This appeal is from the decision of the Patent and Trademark Office Board of Appeals affirming the rejection of claims 3-5, 12-22, and 27 in application serial No. 772,-421, filed October 31, 1968, for “Organometallic Complexes As Alkylaromatic Oxidation Catalysts.” We reverse.
The Invention
The claimed invention involves a method of catalytically oxidizing secondary or tertiary alkylaromatic hydrocarbons to form a reaction mixture comprising the corresponding hydroperoxides. The method employs as the catalyst an organometallic complex formed between hexaalkylphosphoramides and metal salts, the complex having the formula MX„(HAPA)m, wherein HAPA is a hexaalkylphosphoramide, MX is a metal salt, m is an integer of from 1 to 8, and n is an integer of from 1 to 4.
In summarizing their invention, appellants state in their specification:
*500It has now been found, in accordance with the present invention, that organometallic complexes formed between metal salts, preferably those derived from transition metals, (including metals of the lanthanide and actinide series), and hexaalkylphosphoramides are effective catalysts in the oxidation of secondary and tertiary alkylaromatic hydrocarbons. Certain of these catalysts, and particularly those derived from metal salts of the lanthanide series, are especially effective in forming the hydroperoxides of the alkylaromtic[sic] hydrocarbons to the exclusion of other hydrocarbon oxidation products, thus providing the hydroperoxides in high yields at increased conversion rates.
The products produced by this process are described in appellants’ specification as follows:
[T]he oxidation products of the instant process are generally, alcohols, aldehydes, ketones, hydroperoxides, or mixtures thereof. Of these various products, maximization of the formation of the hydro-peroxides is generally preferred * * *. Accordingly, as a preferred embodiment of this invention, it has been discovered that certain of the various metals * * are particularly effective as catalysts in the preparation of hydroperoxides from secondary and tertiary alkylaromatic compounds * * *. These metals preferentially give yields of over 90 percent hydroperoxides to the exclusion of other oxidation products at conversion rates of at least about 4 percent per hour, and in many cases as high as 20 to 25 percent per hour. In the case of those remaining metals which yield lesser amounts or no hydroperoxides in the final product, while applicants do not wish to be bound by any particular theory, it is believed that they too yield hydroperoxides which are then rapidly decomposed by the catalyst complex to form aldehydes, ketones and the like. [Emphasis added.]
Claims 22 and 27 are illustrative and read as follows:
22. The process according to Claim 27 wherein the oxidation is carried out in the added presence of a hydroperoxide.
27. In the process for the catalytic oxidation of secondary or tertiary alkylaromatic hydrocarbons of the formula
wherein R is lower alkyl; Rj is lower alkyl or hydrogen; and Ar is an aromatic nucleus selected from the group consisting of phenyl and naphthyl, in the presence of air or oxygen at a temperature of from about 80 to 150 °C to form a reaction mixture comprising the corresponding hydroperoxides, the improvement wherein the catalyst is of the formula
MXn(HAPA)m
wherein HAPA is a hexaalkylphosphoramide, the alkyl moiety of which has from one to thirty carbon atoms; MX is metal salt wherein M is a transition metal cation of Group IB, IIB, IIIB, IVB, VB, VIB, VIIB, VIIIB or IIA of the Periodic Table and X is an inorganic anion of said metal salt; m is an integer of from 1 to 8; and n is an integer of from 1 to 4, wherein the ratio of said catalyst to said alkylaromatic hydrocarbon is from about 0.1 to 5.0 parts by weight of catalyst per 100 parts by weight of alkylaromatic hydrocarbon.
The Rejection
The examiner rejected all of the claims under 35 U.S.C. § 112, first and second paragraphs. However, the board’s rationale for affirming the rejection was directed primarily to the enablement requirement of the first paragraph of section 112. The board considered the question of “whether the claims on appeal read on subject matter as to which the specification is not enabling.” The claims and the specification were compared and it was found:
*501[T]he claims call for the preparation of a reaction mixture comprising the hydro-peroxides, using the metal salt complexes as the catalyst. However, the specification states that not all of the complexes will produce hydroperoxides and neither discloses which of the complexes will not work nor gives any information as to how the operative catalysts might be determined, without undue experimentation. We believe that the specification leaves too much to conjecture, speculation and experimentation and is insufficient in law to support the present claims containing the disputed language. [Emphasis in original.]
In addition, the board specifically pointed to claim 22 as being “inconsistent with claim 27 in light of present Example 6, which indicates that the presence of added hydroperoxide results in a product devoid of the recited ‘corresponding hydroperoxides.’ ” The board went on to state that “insofar as this is a further ground of rejection under 35 USC 112, it is sustained.”
OPINION
Since all of the claims have been rejected under the first and second paragraphs of 35 U.S.C. § 112, we begin with the analysis set forth in In re Moore, 439 F.2d 1232, 1235, 58 CCPA 1042, 1046-47, 169 USPQ 236, 238 (1971):
Any analysis in this regard should begin with the determination of whether the claims satisfy the requirements of the second paragraph. It may appear awkward at first to consider the two paragraphs in inverse' order but it should be realized that when the first paragraph speaks of “the invention”, it can only be referring to that invention which the applicant wishes to have protected by the patent grant, i. e., the claimed invention. For this reason the claims must be analyzed first in order to determine exactly what subject matter they encompass. The subject matter there set out must be presumed, in the absence of evidence to the contrary, to be that “which the applicant regards as his invention.”
This first inquiry therefore is merely to determine whether the claims do, in fact, set out and circumscribe a particular area with a reasonable degree of precision and particularity. It is here where the definiteness of the language employed must be analyzed — not in a vacuum, but always in light of the teachings of the prior art and of the particular application disclosure as it would be interpreted by one possessing the ordinary level of skill in the pertinent art. [Footnote omitted, original emphasis.]
We note at the outset that the claim limitation “to form * * * hydroperoxides” must be given effect since we must give effect to all claim limitations. See In re Geerdes, 491 F.2d 1260, 180 USPQ 789 (Cust. & Pat.App.1974); In re Wilder, 429 F.2d 447, 57 CCPA 1314, 166 USPQ 545 (1970). Furthermore, the use of functional language is sanctioned specifically by the third paragraph of section 112. Finally, in this particular case, the functional limitation was inserted in the claims at the specific insistence of the examiner.
We further note that, while the board affirmed the examiner’s rejection of the claims under both the first and second paragraphs of section 112, it stated that the primary issue is “whether the claims on appeal read oh subject matter as to which the specification is not enabling.” This is a section 112, first paragraph issue. In re Geerdes, supra. At any rate, we conclude that the scope of the subject matter embraced by the instant claims is clear and the claims do, in fact, set out and circumscribe a particular area with a reasonable degree of precision and particularity. In re Moore, supra, 439 F.2d at 1235, 58 CCPA at 1046-47, 169 USPQ at 238. Therefore, the rejection under the second paragraph of 35 U.S.C. § 112 is reversed.
Continuing with the analysis described in Moore, supra:
Once having determined that the subject matter defined by the claims is particular and definite, the analysis then *502turns to the first paragraph of section 112 to determine whether the scope of protection sought is supported and justified by the specification disclosure. This first paragraph analysis in itself contains several inquiries. Considering the language of the statute, it should be evident that these inquiries include determining whether the subject matter defined in the claims is described in the specification, whether the specification disclosure as a whole is such as to enable one skilled in the art to make and use the claimed invention, and whether the best mode contemplated by the inventor of carrying out that invention is set forth.
Two of the first paragraph requirements indicated above, i. e., the “description of the invention” and the “best mode” requirements, are relatively simple to comply with and thus will ordinarily demand minimal concern on the part of the Patent Office. * * * What is of maximum concern in any analysis of whether a particular claim is supported by the disclosure in an application is whether that disclosure contains sufficient teaching regarding the subject matter of the claims as to enable one skilled in the pertinent art to make and to use the claimed invention. These two requirements, “how to make” and “how to use” have sometimes been referred to in combination as the “enablement” requirement, but, in one form or another, have been the subject of extended discussion in this court of recent years. The relevant inquiry may be summed up as being whether the scope of enablement provided to one of ordinary skill in the art by the disclosure is such as to be commensurate with the scope of protection sought by the claims. [439 F.2d at 1235-36, 58 CCPA at 1047,169 USPQ at 238-39, original emphasis.]
We cannot agree with the board that appellants’ disclosure is not sufficient to enable one of ordinary skill in the art to practice the invention without undue experimentation. We note that many chemical processes, and catalytic processes particularly, are unpredictable, In re Mercier, 515 F.2d 1161, 1167-68, 185 USPQ 774, 779 (Cust. & Pat.App.1975), and that the scope of enablement varies inversely with the degree of unpredictability involved, In re Fisher, 427 F.2d 833, 839, 57 CCPA 1099, 1108, 166 USPQ 18, 24 (1970). That this particular process is unpredictable is demonstrated further by appellants in their specification. Appellants have disclosed forty examples; one of these examples yields no hydroperoxides in the final product. Also, appellants have expressly indicated in their specification that some of these organometallic complex catalysts “yield * * * no hydroperoxides in the final product.”1
Appellants have apparently not disclosed every catalyst which will work; they have apparently not disclosed every catalyst which will not work. The question, then, is whether in an unpredictable art, section 112 requires disclosure of a test with every species covered by a claim. To require such a complete disclosure would apparently necessitate a patent application or applications with “thousands”2 of examples or the disclosure of “thousands” of catalysts along with information as to whether each exhibits catalytic behavior resulting in the production of hydroperoxides. More importantly, such a requirement would force an inventor seeking adequate patent protection to carry out a prohibitive number of *503actual experiments. This would tend to discourage inventors from filing patent applications in an unpredictable area since the patent claims would have to be limited to those embodiments which are expressly disclosed. A potential infringer could readily avoid “literal” infringement of such claims by merely finding another analogous catalyst complex which could be used in “forming hydroperoxides.”
Having decided that appellants are not required to disclose every species encompassed by their claims even in an unpredictable art such as the present record presents, each ease must be determined on its own facts. In the instant case, appellants’ invention is the use of a complex catalyst comprising a hexaalkylphosphoramide and a transition metal salt to catalyze the oxidation of secondary or tertiary alkylaromatic hydrocarbons to form hydroperoxides. Appellants have, in effect, provided those skilled in this art with a large but finite list of transition metal salts from which to choose in preparing such a complex catalyst. Appellants have actually carried out 40 runs using various transition metal salts and hexaalkylphosphoramides. If one skilled in this art wished to make and use a transition metal salt other than those disclosed in appellants’ 40 runs, he would merely read appellants’ specification for directions how to make and use the catalyst complex to oxidize the alkylaromatic hydrocarbons, and could then determine whether hydroperoxides are, in fact, formed. The process discovered by appellants is not complicated, and there is no indication that special equipment or unusual reaction conditions must be provided when practicing the invention. One skilled in this art would merely have to substitute the correct mass of a transition metal salt for the transition metal salts disclosed in appellants’ 40 runs. Thus, we have no basis for concluding that persons skilled in this art, armed with the specification and its 40 working examples, would not easily be able to determine which catalyst complexes within the scope of the claims work to produce hydroperoxides and which do not.
Since appellants have supplied the list of catalysts and have taught how to make and how to use them, we believe that the experimentation required to determine which catalysts will produce hydroperoxides would not be undue and certainly would not “require ingenuity beyond that to be expected of one of ordinary skill in the art.” Fields v. Conover, 443 F.2d 1386, 1390-91, 58 CCPA 1366, 1372, 170 USPQ 276, 279 (1971).
The dissent’s reliance on In re Rainer, 377 F.2d 1006, 54 CCPA 1445, 153 USPQ 802 (1967), is misplaced. If Rainer stands for the proposition that the disclosure must provide “guidance which will enable one skilled in the art to determine, with reasonable certainty before performing the reaction, whether the claimed product will be obtained” (emphasis in original), as the dissent claims, then all “experimentation” is “undue,” since the term “experimentation” implies that the success of the particular activity is uncertain. Such a proposition is contrary to the basic policy of the Patent Act, which is to encourage disclosure of inventions and thereby to promote progress in the useful arts. To require disclosures in patent applications to transcend the level of knowledge of those skilled in the art would stifle the disclosure of inventions in fields man understands imperfectly, like catalytic chemistry. The Supreme Court said it aptly in Minerals Separation, Ltd. v. Hyde, 242 U.S. 261, 270-71, 37 S.Ct. 82, 86, 61 L.Ed. 286 (1916), in discussing the adequacy of the disclosure of the froth flotation process of ore separation:
Equally untenable is the claim that the patent is invalid for the reason that the evidence shows that when different ores are treated preliminary tests must be made to determine the amount of oil and the extent of agitation necessary in order to obtain the best results. Such variation of treatment must be within the scope of the claims, and the certainty which the law requires in patents is not greater than is reasonable, having regard to their subject-matter. The composition of ores varies infinitely, each one presenting its special problem, and it is obviously impossible to specify in a patent the precise *504treatment which would be most successful and economical in each case. The process is one for dealing with a large class of substances and the range of treatment within the terms of the claims, while leaving something to the skill of persons applying the invention is clearly sufficiently definite to guide those skilled in the art to its successful application, as the evidence abundantly shows. This satisfies the law. Mowry v. Whitney, 14 Wall. [81 U.S.] 620, [20 L.Ed. 860]; Ives v. Hamilton, 92 U.S. 426, [23 L.Ed. 494]; and Carnegie Steel Co. v. Cambria Iron Co., 185 U.S. 403, 436, 437, [22 S.Ct. 698, 46 L.Ed. 968, 985, 986] [Emphasis added.]
Appellants have broadly disclosed a class of catalyst complexes whose use they deem to be part of their invention. But for this disclosure the public may have been deprived of the knowledge of appellants’ process. In this art the performance of trial runs using different catalysts is “reasonable,” even if the end result is uncertain, and we see no reason on this record why appellants should not be able to claim as their invention the broad range of processes which they have discovered. The PTO withdrew a rejection of the claims under 35 U.S.C. § 103, and it appears that persons skilled in this art would know how to perform processes within the scope of the claims, within the ambit of the types and amount of experimentation which the uncertainty of this art makes inevitable.
The kind of “guidance” which the dissent seems to contemplate is unrealistic in view of the nature of the invention. The examples, both operative and inoperative, are the best guidance this art permits, as far as we can conclude from the record.
We note that the PTO has the burden of giving reasons, supported by the record as a whole, why the specification is not enabling. In re Armbruster, 512 F.2d 676, 185 USPQ 152 (Cust. & Pat.App.1975). Showing that the disclosure entails undue experimentation is part of the PTO’s initial burden under Armbruster; this court has never held that evidence of the necessity for any experimentation, however slight, is sufficient to require the applicant to prove that the type and amount of experimentation needed is not undue.
By calling the claimed “invention” the “scope of protection sought” the dissent obscures the problem and frustrates the intended operation of the patent system. Depriving inventors of claims which adequately protect them and limiting them to claims which practically invite appropriation of the invention while avoiding infringement inevitably has the effect of suppressing disclosure. What the dissent seems to be obsessed with is the thought of catalysts which won’t work to produce the intended result. Appellants have enabled those in the art to see that this is a real possibility, which is commendable frankness in a disclosure. Without undue experimentation or effort or expense the combinations which do not work will readily be discovered and, of course, nobody will use them and the claims do not cover them. The dissent wants appellants to make everything predictable in advance, which is impracticable and unreasonable.
We hold that the evidence as a whole, including the inoperative as well as the operative examples, negates the PTO position that persons of ordinary skill in this art, given its unpredictability, must engage in undue experimentation to determine which complexes work. The key word is “undue,” not “experimentation.” See Fields v. Conover, supra.
The rejection of claim 22 as being inconsistent with claim 27 in light of Example 6 is also reversed. First, it is not clear on this record whether the examiner actually made a separate rejection of claim 22 on this ground. If the examiner did not make such a rejection, then appellants could not acquiesce in the rejection as the board concluded.
Second, there is no reason to believe that the product recited in Example 6 is, in fact, devoid of hydroperoxides. Run 7 (Table I) and the fourth run in Example 8 (Table VI) both use the exact same metal salt, albeit a *505different alkylaromatic hydrocarbon starting material, as in Example 6 and hydroperoxides are produced in both cases. Example 6 merely states that the white solid material produced in the process “was identified as actaldehyde [sic].” Example 6 clearly does not expressly state that no hydroperoxides were produced. Nor does it implicitly so state in view of the well-known fact that products of organic chemical reactions are almost never produced in a 100% yield but are generally contaminated with other side products. We believe that one of those side products may be a hydro-peroxide in view of the fact that hydroperoxides were produced in other runs involving the same metal salt catalyst.3 Appellants may not have believed it necessary to state that hydroperoxides were, in fact, a (minor) product of Example 6 since the claims as originally filed did not require that appellants’ process “form hydroperoxides.”4
Finally, there is no record evidence to establish that the presence of hydroperoxides in Example 6 results in a product which is devoid of the recited “corresponding hydroperoxides.” Because of this lack of record evidence, we discern no inconsistency between claims 22 and 27 in light of Example 6, Accordingly, the decision of the board is reversed.
REVERSED.