United States: Claim Construction Analysis Begins And Remains Centered On The Language Of The Claims Themselves

In Braintree Laboratories, Inc. v. Novel Laboratories, Inc., No. 13-1438 (Fed. Cir. Apr. 22, 2014), the Federal Circuit affirmed the district court's validity finding, reversed the district court's claim construction of the claim term "clinically significant electrolyte shifts," vacated the district court's SJ of infringement, and remanded for further factual findings on the issue of infringement.

Braintree Laboratories, Inc. ("Braintree") holds U.S. Patent No. 6,946,149 ("the '149 patent"), directed to a composition for inducing purgation of a patient's colon in preparation for a colonoscopy.  The commercial embodiment of the '149 patent is Braintree's SUPREP® Bowel Prep Kit ("SUPREP").  Upon learning that Novel Laboratories, Inc. ("Novel") had filed an ANDA to market a proposed generic copy of SUPREP, Braintree filed an action for infringement of the '149 patent against Novel.  In response, Novel asserted counterclaims of noninfringement and invalidity.  After construing claim terms, the district court granted SJ of infringement in favor of Braintree and found that the '149 patent was valid. 

On appeal, Novel challenged the district court's (1) construction of the claim terms "purgation" and "clinically significant electrolyte shifts"; (2) failure to find U.S. Patent No. 4,975,286 ("Hechter") anticipated the claims of the '149 patent; (3) failure to find the asserted claims of the '149 patent obvious in light of the prior art; and (4) failure to find the claim term "purgation" indefinite.

Considering the district court's construction of "purgation" as "an evacuation of a copious amount of stool from the bowels after oral administration of the solution" and Novel's argument relying on evidence from the specification that the claim term "purgation" should be interpreted instead as "cleansing," the Federal Circuit found Novel's arguments unpersuasive.  Slip op. at 5 (citations omitted).  The Court stressed that claim construction must be centered on the claims themselves, and that while cleansing was the goal specifically articulated in the specification, it was not a claim requirement.  The Court also concluded that Novel's reliance on the claim term "effective amount" was also misplaced because "effective amount" only required purgation and not a full cleansing.  Moreover, the Court concluded that Braintree's statement in its postissuance patent term extension request, in which it stated that SUPREP is a product for "cleansing (i.e., purging)," did not constitute a clear and unmistakable disavowal and did not redefine "purgation."  Id. at 6 (citation omitted).

"In construing claims, the analytical focus must begin and remain centered on the language of the claims themselves, for it is that language that the patentee chose to use to 'particularly point[] out and distinctly claim[] the subject matter which the patentee regards as his invention.'"  Slip op. at 7 (alterations in original) (quoting Interactive Gift Express, Inc. v. Compuserve Inc., 256 F.3d 1323, 1331 (Fed. Cir. 2001)).

In reversing the district court's construction of the term "clinically significant electrolyte shifts," the Court emphasized its precedent that "the patentee's lexicography must govern the claim construction analysis."  Id. at 9 (citing Phillips v. AWH Corp., 415 F.3d 1303, 1316 (Fed. Cir. 2005) (en banc)).  The Court disagreed with the district court's construction because it modified the specification's clear language.  Accordingly, the Court reversed the district court's construction and construed "clinically significant electrolyte shifts" consistent with the inventor's clear definition of the term in the specification. 

Because the district court correctly construed "purgation" as not requiring a full cleanse, the Court affirmed the district court's finding that one (half-dose) bottle of SUPREP practiced this claim limitation.  The Court concluded, however, that the district court's finding that SUPREP practiced the "wherein the composition does not produce any clinically significant electrolyte shifts" limitation was based on its erroneous construction of the term "clinically significant electrolyte shifts," its importation of the preamble term "a patient" into the limitation, and its subsequent improper construction of the term as "one or more patients."  Id. at 10 (citations omitted).  The Court determined that "a patient" should mean a patient population because this definition is consistent with the specification's language.  Since the record showed that at least some patients experienced alterations in blood chemistry outside the normal upper or lower limits of their normal range, the Court held that there remained a genuine issue as to whether SUPREP avoids producing any clinically significant electrolyte shifts in a patient population.  Accordingly, the Court vacated the district court's SJ of noninfringement and remanded for further factual findings.

Turning to invalidity, the Court considered the prosecution history of the '149 patent and both parties' expert witnesses' statements, and found Novel's arguments that the asserted claims were anticipated by Hechter were flawed for three reasons.  First, the Court found that Hechter did not actually disclose administration of the one-liter solution to the patient.  Second, the Court found that while, theoretically, the initial one-liter solution taught in Hechter could be hypertonic in a patient, Novel had no evidence disclosing that the mixture had actually been tested in patients.  Third, Hechter actually taught away from administering a hypertonic solution by stating that its solution needed to be isotonic.  Novel also argued that the combination of sixteen prior art references, including Hechter, rendered the asserted claims of the '149 patent obvious.  The Court concluded that Novel "failed to prove a 'plausible rational[e] as to why the prior art references would have worked together.'"  Id. at 15-16 (alteration in original) (quoting Power-One, Inc. v. Artesyn Techs., Inc., 599 F.3d 1343, 1352 (Fed. Cir. 2010)).  Thus, the Court concluded that the district court did not err in finding nonobviousness. 

Finally, Novel argued that the claim term "purgation" was indefinite because the term "copious" lacked any clear definition in the district court's construction.  Unpersuaded by Novel's argument, the Court emphasized that the word "copious" was only used in the district court's construction and not in the claim, and that such descriptive words are commonly used in patent claims.  In addition, the Court explained that a descriptive word like "copious" would not be indefinite to one skilled in the art in this context.  Thus, the Court dismissed Novel's indefiniteness challenge.

Accordingly, the Court affirmed the district court's claim construction of "purgation" and finding that the asserted claims of the '149 patent are valid, reversed the district court's claim construction of the term "clinically significant electrolyte shifts," vacated the district court's SJ of noninfringement, and remanded for further proceedings.

Judge Dyk agreed that the district court erred in its construction of "clinically significant electrolyte shifts."  While Judge Dyk thought that Novel established noninfringement as a matter of law under the correct "clinically significant electrolyte shifts" construction, he nevertheless joined the remand decision on that issue.  Judge Dyk further agreed that the asserted claims of the '149 patent were not invalid.  However, Judge Dyk dissented from the majority's conclusion that Novel's ANDA met the volume limitation of the asserted claims.  Particularly, Judge Dyk cited the Court's precedent that an ANDA cannot infringe an asserted patent when the FDA-approved dose is not the dose claimed in the patent.  Accordingly, he concluded that Novel's ANDA that sought approval for a two-bottle dose to induce purgation did not infringe the '149 patent, which claims a one-bottle dose regimen.  Additionally, Judge Dyk found that even without the Hatch-Waxman issue, the specification of the '149 patent and Braintree's own expert made clear that the invention was directed at "small volume" solutions of 100-500 mL total, not large volume solutions that could be divided into 100-500 mL administrations.  Therefore, Judge Dyk concluded that Novel's ANDA with the 946 mL regimen did not meet the volume limitation and could not infringe the '149 patent.

Judge Moore joined the majority opinion, but dissented from the majority's construction of the term "a patient" and concluded that the plain and ordinary meaning of the term, based on the Court's precedent on the meaning of "a," should be one or more patients.  Judge Moore concluded that nothing in the specification of the '149 patent or its prosecution history defined "a patient" as a plural "patient population" contrary to the words of the claim.  Judge Moore expressed her understanding of the majority's concern that construing "a patient" to be singular would result in finding noninfringement, even if 99 patients out of 100 experienced clinically significant electrolyte shifts, as long as one patient did not.  However, according to Judge Moore, this is a question of damages, not infringement, and the majority should not rewrite the claim language to avoid this unwanted outcome.

This article previously appeared in Last Month at the Federal Circuit, May 2014.

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