Whither the Meaning of "a" as a Claim Term
By Kevin E. Noonan --
Every once in a while a Federal Circuit panel construes a common claim term contrary to how it has been construed in prior precedent, usually based on the particular situation or circumstance the Court is addressing and consistent with the scope and meaning of the claim as supported by the claim term's plain meaning, use in the specification, and prosecution history. And as a consequence, commentators, pundits, and CLE providers create a flurry of activity surrounding whether there is now a new rubric of patent claim construction thus created (along with dire warnings that only if patent practitioners adhere to the recommendations arising from this "new" precedent can valid claims be acquired). Such an instance has arisen in the Court's Braintree Labs v. Novel Labs case, involving the meaning of the shortest claim limitation, the indefinite article "a."
This is an ANDA case relating to the product SUPREP® Bowel Prep Kit, a colonic purgative used in preparation for colonoscopies or other procedures requiring a clean inner lumen of the colon. This product is a combination of magnesium sulfate, potassium sulfate, and sodium sulfate, and has as an advantage over prior art products that it can be administered in relatively small amounts (100-500 mL) but does not cause severe shifts in electrolyte levels, which in prior art products had produced "heart failure, kidney failure, neurological impairment, and even death." Claim 15 of U.S. Patent No. 6,946,149 is representative:
A composition for inducing purgation of the colon of a patient, the composition comprising from about 100 mL to about 500 mL of an aqueous hypertonic solution comprising an effective amount of Na2SO4, an effective amount of Mg SO4, and an effective amount of K2SO4, wherein the composition does not produce any clinically significant electrolyte shifts and does not include phosphate. (Italics in original, indicating claim terms construed by the District Court.)
The District Court construed certain claim terms, granted summary judgment of infringement against ANDA filer Novel Labs, and held that the claims were not invalid for indefiniteness, anticipation, or obviousness over certain prior art.
The Federal Circuit affirmed in part, reversed in part, vacated in part, and remanded, in an opinion by (now Chief) Judge Prost, joined in part by Judges Dyk, who filed an opinion dissenting in part to a portion of the majority opinion; Judge Moore dissented. The opinion affirmed construction of the term "purgation" to mean less than complete colonic cleansing using 100-500mL of the composition (the kit contained 473 mL bottles that were diluted before use; it was uncontested that both bottles were needed for complete cleansing). The opinion held the District Court's construction of the term "clinically significant electrolyte shifts" was incorrect by including "other untoward effects" along with "alterations in blood chemistry that are outside the normal upper or lower limits of their normal range or other untoward effects." Rather, the opinion adopted a construction that limited the claim to mean ""alterations in blood chemistry that are outside the normal upper or lower limits of their normal range or other untoward effects." This change did not alter the correctness of the District Court's determination regarding Novel's failure to establish invalidity on anticipation, obviousness, or indefiniteness grounds, however.
The third construed claim term, the meaning of "a patient," did require the panel to vacate the lower court's grant of summary judgment of infringement to the patentee however. First, the District Court imported the term "a patient" (words contained in the preamble) into their construction of the "clinically significant electrolyte shifts" term and application of the construed claims to the accused infringing article. In its application of the claim term the District Court held that the term requires that "clinically significant electrolyte shifts" had been experienced by at least one patient, adopting the conventional construction for the word "a" as meaning "one or more." This construction was incorrect, according to the majority opinion (which Judge Moore did not join) because it would permit the accused infringer to be charged with infringement liability "even if 99 patients out of 100 experienced clinically significant electrolyte shifts, as long as one patient did not." In addition to the illogic of such a conclusion, the majority found support in the language of the specification and the claims, from which the panel majority concluded that the term must mean "the general class of persons to whom the patented compositions are directed, i.e., a patient population" (relying, inter alia, on language from the specification that the "objective was to find a well tolerated orally administered colonic purgative that . . . avoided the risks of upset or electrolyte balance in patients" (emphasis in opinion)). Because there was evidence of record that some individuals actually experienced "clinically significant electrolyte shifts," the panel vacated and remanded to the District Court for "further factual findings" on this issue.
Judge Moore dissented based on this construction of the word "a" as it modifies the word "patient" in the claims. According to her dissent, Judge Moore believes that the plain meaning of the word must be "one or more than one" and that the majority was in error in construing the term to exclude "one" patient. She cited precedent for this position, including 01 Communique Lab., Inc. v. LogMeIn, Inc., 687 F.3d 1292, 1297 (Fed. Cir. 2012); SanDisk Corp. v. Kingston Tech. Co., Inc., 695 F.3d 1348, 1360–61; Baldwin Graphic Sys., Inc. v. Siebert, Inc., 512 F.3d 1338, 1342 (Fed. Cir. 2008); Tivo, Inc. v. EchoStar Commc'ns Corp., 516 F.3d 1290, 1303–04 (Fed. Cir. 2008); and Insituform Techs., Inc. v. Cat Contracting, Inc., 99 F.3d 1098, 1105–06 (Fed. Cir. 1996) that "a" means "one or more than one" absent inventor lexicography or express disclaimer of scope, citing Thorner v. Sony Computer Entm't Am. LLC, 669 F.3d 1362, 1365 (Fed. Cir. 2012). She also found far less express use of the term "patient" solely in the plural in the specification or prosecution; indeed, her dissent cited several instances where the patentee used the singular ("a patient" or "a recipient") instead of the plural in this regard. Judge Moore disregarded the majority's concern with their hypothetical that the construction she advanced would find infringement if "99 out of 100 patients experienced clinically significant electrolyte shifts," which her opinion dismissed as being "a question of damages, not infringement," citing precedent to the effect that sporadic or "rare" infringement does not purge infringement but rather lowers the amount of damages for the infringement. In the context of ANDA litigation, Judge Moore realized that her interpretation could lead to the unpalatable consequence that a formulation that only avoids "clinically significant electrolyte shifts" in as little as one patient would be infringing and subject to the "de facto injunction" provided by the Hatch-Waxman Act.
Aberrant constructions of the word "a" have arisen before in the Federal Circuit's jurisprudence, including the case of Abtox v. Exitron (Fed. Cir. 1997). In that case, the question was whether a claim reciting "a metallic gas-confining chamber" in claim 3 of U.S. Patent No. 4,931,261 encompassed embodiments comprising a second chamber:
Apparatus for sterilization of medical devices and materials in a gas plasma comprising
a metallic gas-confining chamber having a non-metallic portion,
a microwave energy source including a microwave cavity positioned to couple microwave energy into said chamber through said non-metallic portion, and
means for holding said medical devices and materials to be sterilized within said chamber volume and away from said microwave cavity, and including a perforated electrical shielding member positioned within said chamber and in close proximity to said microwave energy source to provide a portion of the internal volume of said chamber shielded from and away from said microwave energy providing a field free zone containing said devices and materials.
In that case, the Federal Circuit held, in an opinion by Judge Rader, joined by Judges Mayer and Michel, that the term "a metallic gas-confining chamber" did not encompass a device having separate chambers for the medical devices to be sterilized and the source of neutral particle plasma. The Court based its unanimous decision on the language of the examples and drawings contained in the specification, which showed that embodiments of the claimed device comprising microwave excitation of a gas to produce plasma only comprised a single chamber and thus the word "a" did not have its ordinary meaning of "one or more." The absence of express disclaimer (because this interpretation clearly relied on inference) or lexicography led some to opine that the Court had altered its traditional interpretation of the term, and resulted in (perhaps felicitously) more precise definitions in patent specifications where the term "a" was intended to mean one or more."
The exclusion of "one" from the construction of the word "a" in the Braintree case has likewise raised concerns, in this case for the Biotechnology Industry Organization (BIO) and the Pharmaceutical Researcher and Manufacturers of America (PhRMA), who have filed an amicus brief urging the Federal Circuit to rehear the issue (by the panel or en banc). According to their brief, the panel majority's construction "creates a conflict with [prior] precedent," "ignores basic science [in its rationale}," and "upset settled expectations [that] under[lie] enormous investment." The brief recites the same cases cited by Judge Moore in her dissent and more, and asserts that by not addressing Judge Moore's arguments the panel majority "provided no guidance for determining when its new rule of construction will apply" or provided "any other apparent limit on how far the majority's new rule extends" (and then recited the many other articles that could fall within this purportedly new rule of construction). The brief rebuts the "absurdity" rationale proffered by the majority by noting that "not all drugs work for all people," exemplifying this statement with the success or lack thereof of the combination of caffeine, aspirin, and acetaminophen at alleviating migraines (which is not effective for all migraine sufferers). The brief foresees additional needs for litigation in many other patent cases to determine infringement under circumstance where a substantial proportion of a "population" would not respond to a drug (noting classes of drugs, such as anticancer drugs for which there are a significant proportion of patient populations who are non-responders). Finally, the brief expounds on the "unsettled expectations" produced (in its members and otherwise) by the Court's decision in this case.
Whether or not this case is reviewed by the panel, the full Federal Circuit Court of Appeals, or even the Supreme Court, its claim construction decision once again illustrates the difficulties inherent in deciding the scope and meaning of claim terms in view of each patent's unique specification and prosecution history. Perhaps that is the lesson for these "outlier" claims: that there are no absolutes in claim construction upon which the patent drafter can rely, and each claim should be scrutinized during prosecution and drafting with a view that a court may at some later date need to determine what the claims were intended to exclude. Which is not such a bad way to craft or prosecute patent claims.
Braintree Laboratories, Inc. v. Novel Laboratories, Inc. (Fed. Cir. 2014)
Panel: Circuit Judges Dyk, Prost, and Moore
Opinion for the court by Circuit Judge Prost; opinion concurring in part, dissenting in part, and concurring in the result by Circuit Judge Dyk; dissenting opinion by Circuit Judge Moore