Patent’s Prosecution History Informs the Meaning of the Claim Language, Saving them from Invalidity

Kaken Pharmaceutical Co., Ltd. v. Iancu, [2018-2232] (March 13, 2020), the Federal Circuit   reversed the PTAB’s claim construction, and vacated its determination that the challenged claims of U.S. Patent No. 7,214,506 on a method for treating onychomycosis were unpatentable as obvious.

Kaken proposed that the phrase “treating a subject having onychomycosis” means “treating the infection at least where it primarily resides in the keratinized nail plate and underlying nail bed.” The Board rejected Kaken’s construction as too narrow, concluding that “the express definition of onychomycosis includes superficial mycosis, which in turn is expressly defined as a disease that lies in the skin or visible mucosa.

The Federal Circuit found that the prosecution history—which includes, specifically, statements made by Kaken to overcome a rejection and the examiner’s statements explaining withdrawal of the rejection based on those statements — provides decisive support for limiting the claim phrase at issue to a plate-penetrating treatment of an infection inside or under the nail plate.  A patent’s prosecution history can “inform the meaning of the claim language by demonstrating how the inventor understood the invention and whether the inventor limited the invention in the course of prosecution, making the claim scope narrower than it would otherwise be.  Particularly useful are “express representations made by or on behalf of the applicant to the examiner to induce a patent grant,” which include “arguments made to convince the examiner that the claimed invention meets the statutory requirements of novelty, utility, and nonobviousness.”  The Federal Circuit said that Kaken’s statements during prosecution, followed by the examiner’s statements, make clear the limits on a reasonable understanding of what Kaken was claiming.

The Federal Circuit thus reversed the Board’s claim construction, and vacated the determination of obviousness based upon the erroneous construction.

Prosecution History Doesn’t Have to Rise to the Level of Disclaimer to Inform the meaning of the Disputed Claim Term

In Personalized Media Communications, LLC, v. Apple Inc., [2018-1936] (March 13, 2020), the Federal Circuit reversed the Board’s construction of a claim term of U.S. Patent No. 8,191,091 ON methods for enhancing broadcast communications, vacating the anticipation and obviousness determinations of the corresponding claims, and affirmed the remainder of the Board’s determinations of anticipation and obviousness.

The Federal Circuit noted that the prosecution history, in particular, may be critical in interpreting disputed claim terms because it contains the complete record of all the proceedings before the Patent and Trademark Office, including any express representations made by the applicant regarding the scope of the claims.  Accordingly, even where prosecution history statements do not rise to the level of unmistakable disavowal, they do inform the claim construction.

At issue was the meaning of “an encrypted digital information transmission including encrypted information,” and in particular whether this term is limited to digital information or can also include analog information.  The Federal Circuit began its analysis with the claim language, noting that the claims use the adjective “digital” to describe the “information transmission,” thus supporting the view that the information is, in fact, digital. On the other hand, the Federal Circuit added, the claims do not say “entirely digital.”

Although the Federal Circuit agreed that with the Board that the specification’s broad definition of “programming” could encompass analog signals, it did not agree that it necessarily requires them. Instead, the definition is largely agnostic to the particular technology employed.

The Federal Circuit turned to the specification, finding some relevant statements, but noting that they are not definitional; instead, they are merely illustrations that use open-ended, permissive phrases such as “usually,” “for example,” and “with capacity for.” And when considered in the context of the more than 280 columns of text in the specification of the ’091 patent, these two passages fall far short of defining the relevant terms through repeated and consistent use.

Finally, the Federal Circuit turned to the prosecution history.  While the Board found the prosecution history inconclusive, the Federal Circuit disagreed, noting that even where prosecution history statements do not rise to the level of unmistakable disavowal, they do in-form the claim construction.  The Federal Circuit said an applicant’s repeated and consistent remarks during prosecution can define a claim term—especially where, as here, there is no plain or ordinary meaning to the claim term and the specification provides no clear interpretation.  The Federal Circuit found that the Board erred by effectively requiring the prosecution history evidence to rise to the level of a disclaimer in order to inform the meaning of the disputed claim term, adding the prosecution history provides persuasive evidence that informs the meaning of the disputed claim phrase and addresses an ambiguity otherwise left unresolved by the claims and specification.

Because the Federal Circuit concluded that the disputed claim term was limited to all-digital signals, it reversed the Board’s unpatentability determination for those claims.

“Merely Tangential” Exception to Prosecution History Estoppel Saved “Inartful” Amendment from Barring Infringement by Equivalents

In Eli Lilly and Co. v. Hospira, Inc., [2018-2126, 2018-2127] (August 9, 2019), the Federal Circuit reversed the district court’s finding of literal infringement in the Hospira Decision as clearly erroneous in light of the court’s claim construction of “administration of pemetrexed disodium,” but affirmed the district court’s finding of infringement under the doctrine of equivalents.

Lilly markets the compound pemetrexed in the form of a disodium salt as Alimta®, for treating certain types of non-small cell lung cancer and mesothelioma. This product was covered by U.S. Patent 7,772,209. Hospira and Dr. Reddy’s each filed ANDA applications to market competing

With respect to the finding of literal infringement, Hospira argued that it cannot literally infringe the claims of the ’209 patent because intravenous administration of pemetrexed ditromethamine dissolved in saline—a solution which contains pemetrexed and chloride anions alongside sodium and tromethamine cations—is not “administration of pemetrexed disodium.” The Federal Circuit agreed, finding that “[i]t was clearly erroneous for the district court to hold that the ‘administration of pemetrexed disodium’ step was met because Hospira’s pemetrexed ditromethamine product will be dissolved in saline before administration. A solution of pemetrexed and chloride anions and tromethamine and sodium cations can-not be deemed pemetrexed disodium simply because some assortment of the ions in the solution consists of pemetrexed and two sodium cations.” The Federal Circuit concluded that to literally practice the “administration of pemetrexed disodium” step under the district court’s claim construction, the pemetrexed disodium salt must be itself administered.

With respect to the Doctrine of Equivalaents, the main dispute was whether prosecution history estoppel prevented Lilly from claiming that the administration of pemetrexed ditromethamine was an infringing equivalent to administering pemetrexed disodium. During prosecution, Lilly amended the claims from “an antifolate” to “pemetrexed disodium.” Lilly conceded that this was a narrowing amendment, and that it was made for reasons of patentability. However, Lilly argued that the rationale of its amendment bore “no more than a tangential relation to the equivalent in question.”

Lilly argued that the district court properly held that the reason for its amendment was to distinguish pemetrexed from antifolates generally and that the different salt type is a merely tangential change with no consequence for pemetrexed’s administration or mechanism of action within the body. The Federal Circuit agreed with Lilly. Noting that “tangential” meant “touching lightly or in the most tenuous way,” the Federal Circuit said that the reason for the amendment was to distinguish methotrexate. Under these circumstances the particular type of salt to which pemetrexed is complexed relates only tenuously to the reason for the narrowing amendment, which was to avoid methotrexate . The Federal Circuit therefore held that Lilly’s amendment was merely tangential to pemetrexed ditromethamine because the prosecution history, in view of the ’209 patent itself, strongly indicates that the reason for the amendment was not to cede other, functionally identical, pemetrexed salts.

The Federal Circuit also found support in the prosecution record, noting that Lilly’s amendment, inartful though it might have been, was prudential in nature and did not need or intend to cede other pemetrexed salts. Because the references specifically mentioned pemetrexed the Federal Circuit saiad that narrowing “antifolate” to “pemetrexed disodium” could not possibly distinguish the art cited in the obviousness ground of rejection.

Lilly’s burden under Festo was to show that pemetrexed ditromethamine was “peripheral, or not directly relevant,” to its amendment, and the Federal Circuit concluded it had done so.

The Federal Circuit also rejected arguments that the disclosure-dedication rule prevented a finding of infringement under the docitrine of equivavlents, agreeing with Lilly that the ’209 patent does not disclose methods of treatment using pemetrexed ditromethamine, and, as a result, Lilly could not have dedicated such a method to the public.

Because neither prosecution history estoppel nor the disclosure-dedication rule bars Lilly from asserting infringement through equivalence, the Federal Circuit affirmed the judgement of infringement.

Amendment of Claims in Parent Application Do Not Apply to Continuation Claims that do not have the Amended Language

In Sanofi v Watson Laboratories, Inc., [2016-2722, 2016-2726](November 9, 2017), the Federal Circuit affirmed the district court’s final judgment rejecting the obviousness challenge to claims 1–6, 8–13, and 16 of the U.S. Patent No. 8,410,167; finding inducement of infringement, by both
defendants, of all of those claims except claim 5; and finding infringement by both defendants of claims 1–3, 5-9, and 12–15 of U.S. Patent No. 8,318,800, and by Watson of claims 10 and 11 as well.

On appeal, Watson and Sandoz challenge the district court’s inducement
finding as to the ’167 patent, the district court’s rejection of their obviousness challenge to that patent, and the district court’s rejection of their prosecution disclaimer argument for limiting the scope of the ’800
patent claims.

On the inducement issues, the Federal Circuit said that it reviews the district court’s finding of inducement based on encouragement and inferred intent for clear error, which the Federal Circuit found was absent.  The Federal Circuit noted that the label directed medical providers to information identifying the desired benefit for only patients with the patent-claimed risk factors.  The Federal Circuit rejected Watson and Sandoz argument that substantial noninfringing uses not forbidden by the
proposed labels prevented a finding of intent to encourage an infringing use.  The Federal Circuit found no legal or logical basis for the suggested limitation on inducement.

On the obviousness issue, Watson and Sandoz only challenged the district court’s finding of no expectation of success.  The Federal Circuit said that although the evidence might well have supported the opposite finding, it could not conclude that the district court clearly erred in its finding.

On the infringement issue, the Federal Circuit rejected the argument that Watson and Sandoz  that the district court erred by failing to limit
the claims of the ’800 patent to exclude polysorbate surfactants.  While while prosecuting the parent application, which issued as U.S. Patent No. 7,323,493, Sanofi amended the sole independent claims
(hence all claims)f so as expressly to exclude pharmaceutical
compositions with a “polysorbate surfactant.”  Based on that amendment,
Watson and Sandoz contend that Sanofi made a “prosecution
disclaimer” that also limits the scope of the claims of the ’800 patent, despite the absence of any limiting language in the ’800 patent’s claims.

The Federal Circuit said that a prosecution disclaimer occurs when a patentee, either through argument or amendment, surrenders claim
scope during the course of prosecution.  But when the purported
disclaimers are directed to specific claim terms that have been omitted or materially altered in subsequent applications (rather than to the invention itself), those disclaimers do not apply.  The general ruling being that a prosecution disclaimer will only apply to a subsequent patent if that patent contains the same claim limitation as its predecessor.

The Federal Circuit observed that in prosecuting the application
that issued as the ’493 patent, was to write an express limitation into the claims: “provided that the pharmaceutical composition does not contain a polysorbate surfactant.” This language does not appear in the ’800 patent claims at issue, and Sanofi did not argue during prosecution that the unamended claim language of the ’493 patent, or the disclosed invention generally, excluded polysorbate surfactants.  The Federal Circuit said that the prosecution followed a familiar pattern:

an applicant adopts an explicit claim-narrowing limitation to achieve immediate issuance of a patent containing the narrowed claims and postpones to the prosecution of a continuation application further arguments
about claims that lack the narrowing limitation.

The Federal Circuit said that without more than exists here, that process does not imply a disclaimer as to claims, when later issued in the continuation, that lack the first patent’s express narrowing
limitation.  The Federal Circuit affirmed the district court’s ruling that the
scope of the claims of the ’800 patent should not be limited so as to exclude polysorbate surfactants.