Ex parte Chowdhury

Informative decision only: persuasive authority, not binding precedent. When a claim recites a Markush group as part of a method or combination and the specification describes the members as useful for the function of the invention because of their similarities, the Board will not sustain an improper Markush grouping rejection merely because the members are structurally different or would differ in other biological functions. Members that would be expected to perform the same function in the context of the claimed invention (here, being quantifiable markers representative of radiation exposure) are substitutable and properly grouped. No prior precedent directly addressed this issue in the decision text; the Board applies In re Harnisch, Multilayer Stretch and MPEP § 2117 and stresses that the context of the claimed invention is of paramount importance. For examiners, a rejection resting on the members' structural dissimilarity or divergent native biological functions, without addressing the function they serve in the claim, will not survive review. For applicants, the decision supports defending a Markush group by showing from the specification the common function the members serve in the claimed method, even if they are structurally diverse. The Board relied on In re Harnisch, 631 F.2d 716 (CCPA 1980), In re Jones, 162 F.2d 479 (CCPA 1947), Multilayer Stretch Cling Film Holdings, Inc. v. Berry Plastics Corp., 831 F.3d 1350 (Fed. Cir. 2016), and In re Oetiker, 977 F.2d 1443 (Fed. Cir. 1992) for the burden. LEGAL TEST OR STANDARD: Per MPEP § 2117.II, a Markush claim contains an improper grouping if (1) the members do not share a single structural similarity or (2) the members do not share a common use. Where the group describes part of a combination or process, the members must be substitutable one for the other with the expectation that the same intended result would be achieved, i.e., alternatively usable for the purposes of the invention (Multilayer Stretch). The Board held that if a group lists a set of things the inventor describes as a subgenus, and the specification describes them as useful for the function of the invention because of their similarities, their inclusion is not improper. The examiner bears the initial burden of a prima facie case. TRIGGERING FACTS: Method-of-treatment claims recited lists of miRNAs as markers, with levels measured in serum before and after treatment to indicate treatment effectiveness. The Examiner found the miRNAs structurally different (different nucleotide sequences) and not of a recognized class, but acknowledged they are all disclosed as correlated with radiation exposure and are transcribed and processed the same way. The specification identifies them as quantifiable and as increasing or decreasing in response to radiation exposure, and individual miRNA functionality is not contemplated in the claimed invention. The common function in the claim was not disputed. KEY QUOTE: "What both of these cases make clear, particularly in view of the Federal Circuit's holding in Multilayer Stretch, quoted above, is that, if a recited Markush group lists a set of things that the inventor describes as a subgenus, and those things are described in the specification as useful for the function of the invention because of their similarities, then their inclusion in a Markush group is not improper." (p. 8) PRIOR PRECEDENT AFFECTED: No prior precedential or informative decision is directly affected. The Board follows In re Harnisch, 631 F.2d 716 (CCPA 1980), In re Jones, 162 F.2d 479 (CCPA 1947), and Multilayer Stretch Cling Film Holdings, Inc. v. Berry Plastics Corp., 831 F.3d 1350 (Fed. Cir. 2016), and applies MPEP § 2117. PRACTICE TIP: When defending against an improper Markush rejection, cite the specification to show the common function the members serve in the context of the claimed invention, and argue substitutability for that purpose rather than structural similarity or native biological function. Examiners' rejections should be rebutted on this basis.