In January 2018, the US Patent and Trademark Office(USPTO) published its latest revision of the Manual of Patent Examining Procedure (MPEP). With this revision, the USPTO introduced a new (old) ground of rejection – improper Markush grouping – which authorizes examiners to reject a claim for containing an improper listing of alternatives1. This rejection last had its own MPEP section in 1995, but was eliminated with the first revision of the Sixth Edition of the MPEP2. This new-old rejection has the potential to put patent applicants in a difficult situation, requiring them to carve up their patent claims into smaller chunks for examination or concede that the claimed alternatives are not patentably distinct. The first alternative is costly upfront, potentially requiring the filing of several applications to have the full scope of a claim examined. The second alternative could be detrimental down the line when, for example, a patent applicant appreciates the real value of one alternative over the other during testing after the application is filed.
A “Markush” claim, named after the applicant in Ex parte Markush, recites a list of alternatively useable elements3. In Markush, the Commissioner of Patents held that: “where no generic expression exists by which a group of alternative elements can be claimed [,] applicants are permitted to recite the elements in the alternative4.” In the chemical arts, Markush language is frequently used to claim various substituents. For example, the MPEP provides the example R-OH, where R is methyl, ethyl, propyl, or butyl, leading to a claim that covers methanol, ethanol, propanol, and butanol. Other examples may include alternative process steps, or, as the MPEP notes, means for fastening a diaper, e.g., a hook, a loop structure, a snap, and a buckle.
In this latest iteration, the MPEP instructs examiners to reject a Markush claim as containing an improper Markush grouping if the members of the grouping do not share a single structural similarity or a common use5. According to the MPEP, members of a Markush grouping share a single structural similarity when they belong to the same physical, chemical, or art-recognized class6. Members share a common use when they are disclosed in the specification or known in the art to be functionally equivalent in the context of the claimed invention7. The shared structural feature and common use must be considered on the basis of the claimed subject-matter as a whole and not simply on the alternatives in the Markush grouping8. Thus, in the example of R-OH above, the two-prong analysis is conducted based on the similarity or common use of the parent alcohols – methanol, ethanol, propanol, and butanol – and not on the R group substituent of methyl, ethyl, propyl, or butyl. In this case, it may be a distinction with no real difference, but in the case of more complex chemical compounds, considering the compound as a whole may provide a viable option for overcoming the rejection. For example, in Harnisch, a case cited in the MPEP and discussed in more detail below, the appellate court held that claims to coumarin dyestuffs were proper Markush claims where each of the claimed compounds had a common coumarin core with variable substituents and the common use of being dyes.
According to the MPEP, rejections based on an improper Markush grouping should be made in the first action on the merits after presentation of a claim with an improper Markush grouping9. The MPEP also instructs that if the examiner determines that one or more claims include an improper Markush grouping, the examiner should also require the applicant to elect an alternative or group of indistinct alternatives for search and examination (i.e., an election of species)10. Notably, the examiner need not examine the full scope of the claim that falls outside a proper Markush grouping11. Thus, once an examiner believes that a Markush group is improper, the examiner can confine the search and examination of the presented claim to less than its full scope, giving the USPTO incredible latitude in how to examine a claim with purportedly improper Markush groups.
In addition, the MPEP instructs examiners to include suggestions for overcoming the rejection12. In particular, the MPEP instructs examiners to suggest a proper Markush grouping based on the specification or to suggest that the applicant set forth each alternative (or grouping of patentably indistinct alternatives) in a series of independent or dependent claims, which could then presumably be properly restricted under restriction practice13. The MPEP, however, cautions examiners not to suggest any grouping that would not satisfy the written description requirements of 35 U.S.C. §112(a)14. The MPEP indicates that an improper Markush grouping is a “rejection on the merits and may be appealed to the Patent Trial and Appeal Board15.”
The current MPEP and resulting USPTO practice seems contrary to past guidance from its review court, which rebuked the effective practice of refusing to examine the full scope of a single claim. In In re Weber, the United States Court of Customs and Patent Appeals (CCPA, and precursor to the Federal Circuit) reversed and remanded the USPTO’s rejection of claims on the basis of “improper Markush claims and misjoinder under 35 U.S.C. §12116.” Misjoinder relates to the ability of the USPTO to require restriction between “independent and distinct” inventions. Here, the examiner rejected a single claim because it “embraced 24 enumerated independent and distinct inventions” and finally rejected the claims “as being improper Markush claims and for misjoinder under 35 U.S.C. §12117.” On appeal, the CCPA directed its opinion to whether the rejection was proper under §121 because the reasoning of the USPTO “shows that the analysis of the ‘improper Markush claims’ rejection was to be supportive of the rejection under §121 rather than alternative to it18.” The CCPA then held “that a rejection under §121 violates the basic right of the applicant to claim his invention as he chooses19.” In other words, while the USPTO has the authority to restrict the examination of an application to a single invention between claims, the CCPA held that it does not have an authority to reject a claim by refusing to examine the full scope of the claim as originally presented. The CCPA noted that:
“As a general proposition, an applicant has a right to have Each claim examined on the merits. …
If, however, a single claim is required to be divided up and presented in several applications, that claim would never be considered on its merits. The totality of the resulting fragmentary claims would not necessarily be the equivalent of the original claim. Further, since the subgenera would be defi ned by the examiner rather than by the applicant, it is not inconceivable that a number of the fragments would not be described in the specification20.”
Although the CCPA remanded to the Board to consider the issue of whether the rejection was proper on the basis of improper Markush grouping, in a concurring opinion, Judge Rich asserted that it was his view that the USPTO “created a new kind of ‘improper Markush’ rejection based on 35 U.S.C. §121 which we are reversing21.” The new (old) rejection outlined in the current MPEP does not appear to be that different from what the CCPA struck down years ago, other than the USPTO identifying it as a “rejection on the merits.”
Until this new (old) rejection finds its way back to the Federal Circuit, there may be another way to address an improper Markush rejection. There does not appear to be any federal court that has ever invalidated a claim based on an improper Markush grouping. In In re Harnisch, for example, the US Court of Customs and Patent Appeals (CCPA)22 reversed an examiner’s improper Markush grouping rejection23. In Harnisch, the claims were directed to coumarin compounds having the general formula:
The claimed compounds were useful as dyestuffs24. The examiner rejected the claims under 35 U.S.C. §121 as containing an improper Markush grouping25. Recognizing that 35 U.S.C. §121 “does not form the basis for rejection of a claim26,” the Board reversed the rejection under 35 U.S.C. §121 and issued a new rejection under 37 C.F.R. §1.196(b) on the “judicially created doctrine” of improper Markush grouping27. According to the Board, the compounds were “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 group28.”
While the CCPA “recognized the possibility of such a thing as an ‘improper Markush grouping,’” it acknowledged that improper Markush grouping does not have a specific statutory basis and that an applicant has the right to define what it regards as the invention as it chooses, so long as its definition is not indefinite or lacking written description or enablement support29. Reasoning that all of the claimed compounds were dyestuff s sharing a common coumarin core, the CCPA reversed the Board’s rejection30. According to the CCPA, the claimed compounds all belonged to a subgenus, as defined by the applicant, which was not repugnant to scientific classification31. The Markush grouping was therefore proper32. The USPTO’s own examples in the current MPEP section confirm the absence of precedent33. In fact, the only example of an improper Markush grouping that the USPTO provides in the MPEP is a hypothetical example “[b]ased [o]n PCT Search and Examination Guidelines Example 2334.”
Given the limited precedent, it remains to be seen whether the Federal Circuit will affirm a USPTO rejection on this basis. Applicants should nonetheless keep the potential new (old) rejection in mind when drafting patent claims. To avoid the rock-and-hard-place conundrum, applicants may want to draft their specification and claims with an eye toward restriction practice instead of being required to dissect a larger genus claim as an alleged improper Markush group.
1 MPEP §706.03(y), Ninth Edition, Rev. 8, January 2018.
2 Compare MPEP §706.03(y), Sixth Edition, January 1995, with MPEP §706.03, Sixth Edition, Rev. 1, September 1995.
3 Ex parte Markush, 1925 C.D. 126 (Comm’r Pat. 1924)
5 Supplementary Examination Guidelines for Determining Compliance with 35 U.S.C. 112 and for Treatment of Related Issues in Patent Applications (“Supplementary Guidelines”), 76 Fed. Reg. 7162, 7166 (Feb. 9, 2011).
6 MPEP §706.03(y), Ninth Edition, Rev. 8, January 2018.
12 MPEP §706.03(y), Ninth Edition, Rev. 8, January 2018.
13 See MPEP §803.02 (Markush claims may be subject to election of species but not restricted). See also In re Weber, 580 F.2d 455 (C.C.P.A. 1978), infra.
14 MPEP §706.03(y), Ninth Edition, Rev. 8, January 2018.
16 Weber, 580 F.2d at 458.
17 Id. at 456.
18 Id. at 458.
19 Id. at 458-59.
20 Id. at 458.
21 Id. at 459, 461.
22 The US Court of Customs and Patent Appeals was abolished in 1982 when its judges and jurisdiction were transferred to the new US Court of Appeals for the Federal Circuit.
23 In re Harnisch, 631 F.2d 716 (CCPA 1980).
24 Id. at 716-17.
25 Id. at 717.
26 See In re Haas, 580 F.2d 461, 464 (CCPA 1978) (holding that 35 U.S.C. §121 may 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).
27 Harnisch, 631 F.2d at 717-18.
28 Id. at 718.
29 Id. at 721.
30 Id. at 722.
33 MPEP §706.03(y), Ninth Edition, Rev. 8, January 2018 (citing In re Harnisch, 631 F.2d 716 (CCPA 1980) (noting that “[t]he CCPA reversed the Board’s decision and held that the Markush grouping was proper”); Ex parte Dams, Appeal No. 1997-2193, 1997 WL 33123171 (BPAI 1997) (noting that “[t]he Board stated that the examiner erred by failing to treat the compounds of the claims as a whole”); Ex Parte Hozumi, 3 USPQ2d 1059 (BPAI 1984) (noting that “[t]he Board reversed the examiner’s improper Markush grouping rejection of claim 1, once again relying on the Harnisch decision”)).
34 MPEP §706.03(y), Ninth Edition, Rev. 8, January 2018.
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