[T]he preamble constitutes a limitation when the claim(s) depend on it for antecedent basis, or when it "is essential to understand limitations or terms in the claim body."

On December 27, 2012, in C.W. Zumbiel Co. v. Kappos, the U.S. Court of Appeals for the Federal Circuit (Prost, Moore, Wallach*) affirmed the USPTO Board of Patent Appeals and Interferences decision upholding the patent examiner's rejection of certain claims in the inter partes reexamination of U.S. Patent No. 6,715,639, which related to a carton or box for holding containers such as cans and bottles, as obvious under 35 U.S.C. § 103. The Federal Circuit stated:

A claimed invention is unpatentable if the differences between it and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the pertinent art. 35 U.S.C. § 103(a). . . . Obviousness is a question of law, based on four factual inquiries: the scope and content of the prior art, the differences between the prior art and the claimed invention, the level of ordinary skill in the field of the invention, and any relevant objective considerations.

We begin with Graphic's cross appeal which concerns representative independent claims 1 and 13. Graphic argues that these claims are patentable and that the Board erred in affirming the Examiner's rejection of these claims as unpatentable over Ellis in view of German '718. . . . The Board found that Graphic's "assertion that Ellis describes an opening operation in which the carton is initially laid on its side to allow access to the bottom . . . is largely speculative." Substantial evidence supports this finding. . . . The Board found, and we agree, that "providing the finger opening on the top wall of the carton would be a predictable variation that enhances user convenience, as evidenced by German '718, and is within the skill of a person of ordinary skill in the art."

Graphic also argues that it would not have been obvious to one of ordinary skill to use the German '718 fold line to form the dispenser in Ellis. . . . Regardless of German '718's disclosure pertaining to the opening allowing for simultaneous removal and replacement of containers, the Board found: "the broader teaching of German '718 [is] that a fold line can be used so that the cover part can be folded back up again for any desired reason," noting that Graphic incorrectly "presupposes that all of the teachings of German '718 . . . must be incorporated into Ellis," [T]here is substantial evidence indicating Ellis in view of German '718 teaches a perforated line for both tearing and folding. We conclude that the invention disclosed in claim 1 would have been obvious to one of skill in the art in light of the prior art references.

[Graphic] argues that this court [should] find that the Board's construction was not reasonably consistent with the written description of the '639 patent in that Ellis provides "tear line 21 [that] only extends part way across the side end flaps 16, 18 and then is interrupted by cut-out portion 20," unlike the '639 patent. Graphic argues that "one of ordinary skill would construe the term 'free ends' . . . as meaning the distal ends of the side end flaps, rather than a point spaced from the distal ends." Graphic concludes that claim 13 "does not read on the combination of Ellis and German '718, and the Board's affirmation of the rejection based thereon should be reversed." Similarly, Graphic argues that with regard to the "single tear-line" limitation of claim 13, this limitation is not met because Ellis discloses a tear line around the container that is interrupted by the cut-out portion that forms the hand hold.

"Although the PTO gives claims the broadest reasonable interpretation consistent with the written description . . . claim construction by the PTO is a question of law that we review de novo . . . just as we review claim construction by a district court." In this case, the Board's construction of "free ends" is legally correct and was met by the prior art, as was the "single tear-line" limitation. As the PTO noted "[t]he 'end' of a flap is defined by the edge thereof, which includes the edge that defines the cut-out portion 20. We observe that this edge is 'free' in that it is not attached to any other structure." Graphic's argument that "free ends" are the "distal ends of the side end flaps" is unsupported by the plain meaning of the term; the specification does not define "free ends" much less define it in the specific way described by Graphic. Additionally, the "free-end" limitation is met by Ellis; in Ellis, tear line 21 does extend to the free ends of the flaps 16 and 18 irrespective of whether cut-out portion 20 is provided to help define the free end of those side end flaps. . . . Ellis's tear-line goes around the carton, and was therefore a single tear-line. As the Board noted, "the recited single tear line [in claim 13] is formed by a compilation of various tear line segments that are formed across various panels of the carton (i.e., side end flaps, top and sides)."

We turn to Zumbiel's appeal which concerns representative dependent claim 2. Zumbiel argues that this claim is obvious and that the Board erred in affirming the Examiner's finding of patentability. Zumbiel also argues the Board erred in considering preamble claim language. [A]ccording to Zumbiel, the preamble of claims 1, 8, and 13 (and therefore their corresponding dependent claims 2, 9, and 14) "inherently, should not be considered when determining the patentability of those claims relative to the prior art," and the Board erred in so doing. Zumbiel asserts that because "containers" (i.e., the cans within the carton) are recited in the preamble but not in the body of the claim, "containers" cannot be a claimed limitation of the invention. . . .

"A claim's preamble may limit the claim when the claim drafter uses the preamble to define the subject matter of the claim." We construe the preamble as limiting when it is "'necessary to give life, meaning and vitality'" to the claim based on the facts of the case at hand and in view of the claim as a whole. [T]he preamble constitutes a limitation when the claim(s) depend on it for antecedent basis, or when it "is essential to understand limitations or terms in the claim body." Here, "containers" as recited in the claim body depend on "a plurality of containers" in the preamble as an antecedent basis. Therefore, these terms recited in the preamble are limitations as the Board concluded.

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