The Federal Circuit affirms the lower court ruling that “half-liquid” translated from the original Italian “semiliquido” is indefinite in IBSA Institut Biochimique, S.A., Altergon, S.A., IBSA Pharma Inc. v. Teva Pharmaceuticals USA, Inc. (Fed. Cir. July 31, 2020).

IBSA is the owner of U.S. patent no. 7,723,390 and Teva filed an Abbreviated New Drug Application that included a certification of invalidity of that patent. Claim 1 of that patent is

1. A pharmaceutical composition comprising thyroid hormones or their sodium salts in the form of either:

a) a soft elastic capsule consisting of a shell of gelatin material containing a liquid or half-liquid inner phase comprising said thyroid hormones or their salts in a range between 0.001 and 1% by weight of said inner phase, dissolved in gelatin and/or glycerol, and optionally ethanol, said liquid or half-liquid inner phase being in direct contact with said shell without any interposed layers, or

b) a swallowable uniform soft-gel matrix comprising glycerol and said thyroid hormones or their salts in a range between 0.001 and 1% by weight of said matrix.

At issue is the limitation “half-liquid inner phase” and more specifically the meaning of half-liquid as there was no intrinsic record that defined this term:

IBSA pointed out that the Italian Application used the term “semiliquido” in the same places where the ’390 patent used “half-liquid,” and where a certified translation of the Italian Application prepared for IBSA in 2019 used “semi-liquid.” IBSA contended that there is a link between these terms such that a person of ordinary skill in the art (“POSA”) would understand “half-liquid” and “semi-liquid” to be synonyms. The district court disagreed.

The district court also noted that, during prosecution, the applicant proposed a dependent claim using the term “semi-liquid.” This claim depended on an independent claim that used the term “half-liquid.” Although the dependent claim using the term “semi-liquid” was removed by the applicant, the district court reasoned this portion of the prosecution history was “evidence that the applicant did not mean ‘semi-liquid’ when he used the term ‘half-liquid.’”

Similarly, in reviewing the ’390 patent’s specification, the district court determined that citation to pharmaceutical references, including Remington’s Pharmaceutical Sciences, which used the term “semi-liquid,” did not show that “half-liquid” meant “semi-liquid.” Instead, the court reasoned that such citation showed that the applicant knew of the term “semi-liquid” yet intentionally chose not to use it.

These were all fatal flaws to the District Court and the CAFC:

The district court relied on a passage of the specification stating that “[i]n particular, said soft capsule contains an inner phase consisting of a liquid, a half-liquid, a paste, a gel, an emulsion or a suspension comprising the liquid (or half-liquid) vehicle and the thyroid hormones together with possible excipients in suspension or solution,” to determine that a “half-liquid is not, or at least is not necessarily, a gel or a paste.” Decision, 2019 WL 3936656, at *6 (quoting ’390 patent col. 7 l. 65–col. 8 l. 2). Not only do we agree with the district court’s interpretation of this passage, but a second passage reinforces this interpretation. See ’390 patent col. 10 ll. 38–39 (“Soft capsules (SEC) with liquid, half-liquid, paste-like or gel-like inner phase”). These disjunctive lists designate that a “half-liquid” is an alternative to the other members of the list, including pastes and gels.

It can be speculated if the correct translation of the original claim term “semiliquido” had been used in the specification and claims, there would not have been the same problem. Based on the totality of the record (see the citations in the ‘390 patent at col. 7 that both Courts relied upon as well as col. 10 cited by the CAFC) it does seem likely that the claim term would have still been found to be indefinite. Nonetheless, there are some important lessons here. First, pay extra scrutiny to a patent application that has been translated, translators are human and errors occur. Second, if a central part of the invention involves a term or phrase that is not well-defined in the relevant art, particularly one that may have a subjective interpretation, consider defining it in the specification.