RICH, Judge.

This appeal is from the decision of the United States Patent and Trademark Office (PTO) Board of Appeals (board) rejecting, under 37 C.F.R. 1.196(b), claims 1 and 3-8 of appellant's application, serial No. 559,978, filed March 19, 1975, for "Coumarin Compounds," on the sole ground that these claims are "drawn to improper Markush groups." We reverse.

The Invention

The claimed compounds encompass coumarin compounds useful as dyestuffs. Some of them may be used as intermediates to make other dyestuffs. Claim 1 is representative and reads as follows:

1. Coumarin compounds which in one of their mesomeric limiting structures correspond to the general formula

wherein

X represents aldehyde, azomethine, or hydrazone,

R[1] represents hydrogen or alkyl,

Z[1] represents hydrogen, alkyl, cycloalkyl, aralkyl, aryl or a 2-or 3-membered alkylene radical connected to the 6-position of the coumarin ring and

Z[2] represents hydrogen, alkyl, cycloalkyl, aralkyl or a 2-or 3-membered alkylene radical connected to the 8-position of the coumarin ring

and wherein

Z[1] and Z[2] conjointly with the N atom by which they are bonded can represent the remaining members of an optionally benz-fused heterocyclic ring which, like the ring A and the alkyl, aralkyl, cycloalkyl and aryl radicals mentioned, can carry further radicals customary in dyestuff chemistry.

Claims 3-6 depend from claim 1, adding further limitations with respect to the substituents; claim 7 is an independent claim of the same type as claim 1 but of much greater length in naming substituents, and claim 8 depends therefrom as well as from claim 4.

The instant coumarins are said to be useful for dyeing synthetic or natural fibers, plastics, and liquids such as oils and lacquers. Of apparently significant commercial value is the dyeing of either the aqueous or organic based inks preferred in rotary gravure printers for non-textile articles.

Clear shades of yellows to oranges are purportedly achieved with good fastness properties. In addition, a strong chartreuse to yellow fluorescence supposedly occurs upon exposure to either natural or ultra violet light. The fluorescence is said to be especially suitable for tunable dye lasers.

The Rejection

The examiner, relying on no prior art, rejected claims 1 and 3-8 under 35 U.S.C. § 121 "as containing an improper Markush group and misjoinder." More explicit reasons were said to be set forth in the earlier Office Action of May 12, 1976. In that action the examiner enumerated ten species of compounds encompassed by the claims. Beside each group he listed the various PTO class 260 subclasses into which the species fall.

The significance of this segmentation was declared to be twofold. In the examiner's words,

A reference anticipating one member [of the listed groups] would not render any other member obvious under 35 U.S.C. § 103. The members are not so few in number or so closely related that a search and examination of the entire claim cannot be made with [sic, without?] serious burden.

The Board

The board summarily reversed the rejection of the appealed claims under 35 U.S.C. § 121. Citing our decisions in In re Weber, 580 F.2d 455, 198 USPQ 328 (CCPA 1978), and In re Haas, 580 F.2d 461, 198 USPQ 334 (CCPA 1978), decided subsequent to the examiner's rejection, the board stated that " 35 U.S.C. § 121 does not form the basis for rejection of a claim * * *."

A new rejection was then made by the board under 37 C.F.R. 1.196(b), rejecting the claims as "drawn to improper Markush groups." After a lengthy listing of decisions from 1925 to 1953 reviewing "Markush practice," by the Commissioner, the board, and this court, the board expounded its theory of the propriety of its new "improper Markush group" rejection solely on the basis of "judicially created doctrine," as follows (our emphasis):

Applying the facts of this case to the principles enunciated, we find that the members of the Markush groups of the claims do not belong to a known or recognized genus and possess widely different physical or chemical properties. Aside from the obvious fact that the compounds encompassed by the claims are not functionally equivalent, said compounds, considered as a whole, are so dissimilar and unrelated chemically or physically that it would be repugnant to accepted principles of scientific classification to associate them together as a generic group. For example, the types of derivatives encompassed by the Markush claim may include polyfused N-heterocyclics, cyclic, acyclic and aromatic amines, aryloxyalkylamines, amides, sulfonamides, phthalimides, quaternary ammonium salts, phosphorous heterocyclics, phosphates, aldehydes, azomethines, hydrazones, ethers, esters, halogens, alcohols, nitriles, piperidines, furanes, pyrroles, indoles, amongst others. It is clear that on this record the involved compounds cannot be considered functionally equivalent, in fact, some being no more than intermediates for the others. The foregoing is borne out by the record wherein appellant discloses that the various groups or compounds possess different physical or chemical properties. Nowhere in the record has it been established or even alleged that the variety of compounds included within the explicit scope of the claims are recognized by the art as being functionally equivalent. The functional groups involved herein, as exemplified above, are so structurally diverse they would be expected to possess dissimilar and unrelated chemical and physical properties. The mere fact that there is a single structural similarity (i.e., the coumarin group) is not in itself sufficient reason to render all the embodiments functionally equivalent, particularly when the ultimate properties of the final products would not be expected to possess any recognized functional relationship. Thus, the fact that the coumarins are in most part indicated as being dyestuffs (others being intermediates for dyes) is not sufficient, since, depending upon their structure, they may be subject to different modes of application and use.

Appellant's Position

Appellant, picking up the board's statement that its rejection "has basis in judicially created doctrine," as shown by the cases it cited, rather than in the patent statutes, asks this court, first, whether claims can be rejected on a judicially-created doctrine rather than on some statutory basis, such as 35 U.S.C. § 121 on which the examiner relied. If they can, then appellant asks, second, whether the compounds claimed are sufficiently closely related to be joined in the same claim.

On the first point, appellant seems to assume some unstated specific "doctrine" on which the board acted, against which he inveighs, and which he says cannot stand, urging us not to create a "doctrine."

On the second point, appellant discusses the fact situation underlying the appealed claims, showing that the compounds are all dyestuffs, that the members of group X, claim 1, are closely related, that the compounds are all coumarins, and cites two board opinions reversing rejections by the examiner of claims structured similarly to appellant's claims, namely, Ex parte Brouard, 201 USPQ 538 (Bd.App. 1976), and Ex parte Taylor, 167 USPQ 637 (Bd.App. 1969). The former case, like this one, involved a claim 24 to a dyestuff defined by structure containing, inter alia, a substituent "B" the definition of which included a list of alternatives occupying about a column in the USPQ report. The rejection reversed was on the ground of "improper Markush group" and misjoinder of independent and distinct inventions.

The PTO Position

The solicitor's brief contains helpful digests of certain key cases selected from the many which discuss "Markush practice" from its inception in 1924 through 1979. It supports the board's new rejection on the ground the claims are drawn to "improper Markush groups." After stating that "Markush practice" is one of long standing and involves a vast body of precedent, the brief relies primarily on the following contentions: (1) there need not be a specific statutory basis for the rejection, citing by analogy obviousness-type double patenting rejections which are case-law based; (2) the materials set forth in the "Markush group" ordinarily must belong to a recognized physical or chemical class or to an art-recognized class; and (3) the claimed group must not be "repugnant to accepted principles of scientific classification."

A principal factual contention in the solicitor's brief is that appellant's claimed compounds include (1) dyestuffs, (2) intermediates for making dyestuffs, or (3) both, and fails to reveal the utility per se of each compound. However, at oral argument the solicitor announced with admirable candor that, having considered appellant's reply brief, he had concluded that there is in fact no class "(2)" because all of the claimed compounds are dyestuffs though some of them could also be used as intermediates to make still other dyestuffs.

The solicitor also cited authority to the effect that each "improper Markush" case must be decided on the basis of its own facts. He also stated that current PTO "Markush practice" is as set forth in section 706.03(y) of the Manual of Patent Examining Procedure (MPEP), 3d ed., Rev. 46, July 1976, reproduced in full as an appendix hereto.

OPINION

We will first express our views concerning the PTO's reliance on "judicially created doctrine" in its rejection of claims for "improper Markush grouping." Appellant injected this point into the case by contending that the PTO had no right to rely on doctrine because a statutory basis for rejection must be stated. He also seems to contend that there is no "doctrine" and that while this court could create one it should not do so. In consequence, much of the oral argument was involved with the court trying to find out from the solicitor what, if any, "doctrine" was being relied on by the PTO, no clear answer being forthcoming — with good reason.

Upon reflection and consideration of the cases cited by the board, the discussion of those and others by the solicitor, and the recorded history of Markush practice, it appears to us that all of the discussion of "doctrine" is beside the point because there is no "Markush doctrine." Appellant never made clear or specific what "doctrine" he was referring to and the solicitor, justifiably, was unable to point one out to us.

"Markush" was the name of an applicant for patent (Eugene A. Markush) who happened to use in a claim a type of definition of a genus or subgenus by enumeration of species, which he did not devise and which had been used before in patent claims. The examiner considered the claim to be "alternative" in form, objected to it, and Markush petitioned the Commissioner. Assistant Commissioner Kinnan, in Ex parte Markush, 1925 CD 126 (Com.Pat. 1924), approved the form of claim and granted the petition, thus requiring the examiner to examine it for patentability. Thus the name "Markush" became attached to a type of claim expression, and that is all it connotes. As others rang changes on the type of expression used by Markush and approved by Assistant Commissioner Kinnan, further decisions and opinions on petitions and in appeals ensued and a considerable body of case law evolved, approving and disapproving various forms of Markush-type expression, from which cases a number of rules can be deduced. Like other bodies of case law, however, the body pertaining to what may properly be called Markush practice has not been altogether consistent and has evolved through the years. Among the inconsistent decisions, some of them were by this court. In the PTO, one of the changes that took place was the abandonment of the rule against the use of "or" in an enumeration of alternative materials that might be used in a claimed invention, which rule was the basis of the objection giving rise to the Markush decision. A specific example will be found in MPEP 706.03(y). Not long ago, by a Notice under date of May 1, 1974, the PTO set up a "Practice Re Markush-Type Claims" and later incorporated the Notice in MPEP section 803. Since the MPEP revision of July 1978, that practice has not been followed because of two decisions of this court and MPEP 803 now contains this statement:

PRACTICE RE MARKUSH-TYPE CLAIMS

The subject matter formerly under this subtitle has been cancelled in view of the decisions In re Weber et al., 198 USPQ 328 (CCPA 1978); and In re Haas, 198 USPQ 334 (CCPA 1978).

Thus have decisions changed the Markush practice.

It is also clear that Markush practice does not refer to a single rule. As may be seen from MPEP 706.03(y) set forth in the appendix, the PTO has one practice with respect to claims directed to compounds per se and a different one when they are directed to a process or composition involving a combination of steps or ingredients wherein the Markush-type definition-by-enumeration is used in defining a process step or composition element.

In summary, there is no "doctrine" to be considered but only a body of case law, emanating from both "higher" and "lower" authority, not altogether consistent, the latest decisions tending to carry the most weight as precedent.

Coming now to appellant's first contention that the board had no right to rely on "judicially created doctrine," we note that a doctrine, by definition, is, according to Black's Law Dictionary, revised 4th ed., "A rule, principle, theory, or tenet of the law." As is clear from the entire board opinion, what it meant was that it intended to rely on rule, principles, or tenets derivable from the cases it cited which would enable it to determine whether the claims before it were or were not in proper form to be examined for patentability. Our ruling on this point is that it had a perfect right to do so. But there is not one "doctrine" or rule; there are many.

The next questions are whether the board correctly interpreted the facts and whether it correctly applied the rules of law derivable from the cases to the facts. Before considering these questions, we take note of some recent history respecting Markush practice.

In the PTO, patent applications are examined for compliance with the statutory provisions of Title 35, United States Code, as set forth in sections 100, 101, 102, 103, and 112. These are considered to be examinations "on the merits." There are also procedural questions arising under section 121 and related PTO rules concerned with "restriction practice." See MPEP, Chapter 800. As shown by the In re Haas cases, issues arose from PTO refusal to consider on the merits single claims to groups of chemical compounds of broad scope unless each claim was first broken up into a plurality of claims of lesser scope. The first PTO position was that it would neither consider nor reject the claims, thus foreclosing appeal to the board or to this court. After this position was held to be a rejection, the PTO promulgated its May 1, 1974 Notice, which authorized rejection on the basis of § 121, relating to restriction, thus combining the two matters of Markush practice and restriction practice. In Haas II (see note 6, supra), this court held that § 121 could not be used as the basis for rejecting a single claim or compelling its replacement by a plurality of narrower claims before examination on the merits would be made. Haas II was decided at the same time as In re Weber, supra, involving similar issues, and Haas II was decided on the basis of the opinion in Weber. We note that in Weber the majority opinion regarded the "improper Markush grouping" reasoning of the board as having been merely "supportive of the rejection under § 121 rather than alternative to it" and dealt only with the § 121 rejection, reversing it and remanding the case to the PTO for consideration, separately, of the "improper Markush" rejection. The concurring opinion, by the present writer, pointed out with respect to that remand, that there existed a vast body of case law relating to Markush practice. We have not yet heard again from Weber, but the present case comes to us in similar posture. Note that this case involves an improper Markush rejection by the examiner based on § 121 which the board reversed in view of Weber, substituting its own improper Markush rejection based only on judicial precedent and divorced from § 121.

Anent appellant's argument that the board should not be allowed to rely solely on judicial precedent, we think it should be clear from our actions in Weber and Haas II that we there recognized the possibility of such a thing as an "improper Markush grouping." We were and are aware that it does not have a specific statutory basis, as we are aware of an applicant's right to define what he regards as his invention as he chooses, so long as his definition is distinct, as required by the second paragraph of § 112, and supported by enabling disclosure, as required by the first paragraph of § 112. In re Wakefield, 57 CCPA 959, 422 F.2d 897, 164 USPQ 636 (1970); In re Borkowski, 57 CCPA 946, 422 F.2d 904, 164 USPQ 642 (1970).

In the early years of the development of Markush practice, many of the cases involved the problem of clarity — avoiding the uncertainties of alternatives and the like. More recently, the cases have centered on problems of scope, which are related to enablement. Assuming enablement, however, there remains a body of Markush-practice law regarding Markush-type claims, particularly in the chemical field, concerned more with the concept of what might be better described as the concept of unity of invention. At least the term would be more descriptive and more intelligible internationally than is the more esoteric and provincial expression "Markush practice." It is with this unity of invention concept in mind that we approach the propriety of the appealed claims.

Over thirty years ago this court decided In re Jones, 34 CCPA 1150, 162 F.2d 479, 74 USPQ 149 (1947), reversing an "improper Markush group" rejection of claims to chemical compounds which were growth regulating compositions for plants, fungicides, and insecticides. Notwithstanding their various properties, the court found all of the compounds included in the claims were plant growth stimulants, thus having a common function. The court noted that in any Markush group the compounds "will differ from each other in certain respects." It laid down the proposition, with which the PTO agrees in its MPEP, that in determining the propriety of a Markush grouping the compounds must be considered as wholes and not broken down into elements or other components. It also held, in agreement with the board, that each case of this type must be considered on its own facts. Citing Ex parte Clark, 11 USPQ 52 (Com. Pat. 1931), a case decided by the author of the original Markush opinion, it noted that "the inclusion in Markush groups of compounds which differed widely in some respects," namely, aliphatic, aromatic, and aralkyl compounds, had been permitted. It cited Ex parte Dahlen, 42 USPQ 208 (Bd. App. 1938) as permitting the grouping of compounds having the same nuclei but side chains wherein there was a wide variation. It found the claims before it to cover compounds all belonging to a genus of tetralyl compounds having a substituted methyl group at position 6 and ruled that they had a community of properties justifying their grouping which was not repugnant to principles of scientific classification.

We regard the present case as similar to In re Jones, supra, and also the much later decision of the board in Ex parte Brouard, supra, in which the board reversed the examiner's "improper Markush" rejection. We conclude that the board here was factually in error in not recognizing that all of appellant's claimed compounds are dyes, as confirmed by the solicitor's admission. The board's reliance on its notion that some of the claimed compounds are "no more than intermediates" overlooked the now admitted fact that they are dyes as well. Clearly, they are all coumarin compounds which the board admitted to be "a single structural similarity." We hold, therefore, that the claimed compounds all belong to a subgenus, as defined by appellant, which is not repugnant to scientific classification. Under these circumstances we consider the claimed compounds to be part of a single invention so that there is unity of invention as was held to be the case in Ex parte Brouard, supra, 201 USPQ at 540. The Markush groupings of claims 1 and 3-8 are therefore proper.

As stated above, we decide this and like cases on their facts on a case-by-case basis. It should also be clear from what we have said that we adhere to our holdings in In re Weber, supra, and In re Haas (Haas II), supra. Nothing we have said herein is intended to change or modify them in any way; nor do we think anything said could be reasonably construed to have such an effect. The "unity of invention" concept is not to be confused with the "misjoinder under 35 U.S.C. § 121" rejection employed in In re Weber. In Weber we dealt with the use of 35 U.S.C. § 121, which deals only with restriction requirements, to support the rejection of a single claim. Here we are concerned only with the rejection of a single claim on the distinct ground that it is directed to an "improper Markush group." Reference to the widely-recognized concept of "unity of invention" has been made in order to suggest an appropriate term to apply where unrelated inventions are involved — inventions which are truly independent and distinct. This case, we find, does not involve such inventions.

Appellant expressly stated in his brief that no appeal was being taken from the rejection of claim 6 under 35 U.S.C. § 112 or of claim 8 as improperly dependent. In addition, while appellant's reasons of appeal alleged error in the board's supposed dismissal of claims 9-14 and 23-25, this alleged error has not been argued and is therefore deemed abandoned. The appeal with respect to claims 6, 8-14, and 23-25 is therefore dismissed.

The board's rejection of claims 1 and 3-8 as based on "improper Markush groups" is reversed.

REVERSED.

APPENDIX 706.03(y) Improper Markush Group [R-49]

SUBGENUS CLAIM