When Half a Glass Is an Empty Glass

Holding: In IBSA Institut Biochimique, S.A. v. Teva Pharms. USA, Inc., --F.3d__ (Fed. Cir. July 31, 2020), the U.S. Court of Appeals for the Federal Circuit (Judges PROST, Reyna, and Hughes) affirmed the district court’s decision that certain IBSA’s claims were invalid as indefinite.

Background: IBSA’s U.S. Pat. 7,723,390, claim 1, reads: A pharmaceutical composition comprising thyroid hormones or their sodium salts in the form of either:

1. a) a soft elastic capsule consisting of a shell of gelatin material containing a liquid or half-liquid inner phase …, said liquid or half-liquid inner phase being in direct contact with said shell without any interposed layers, or
2. b) a swallowable uniform soft-gel matrix …. (emphasis added.)

The ’390 patent is listed in the Orange Book for the product Tirosint®. IBSA proposed that the term “half-liquid” should be construed as “semi-liquid, i.e., having a thick consistency between solid and liquid.”

The district court first analyzed whether IBSA’s proposed construction was supported by the record and found it was not. IBSA attempted to rely on an Italian priority application, which used the term “semiliquido” wherever the U.S. patent used “half-liquid,” and its certified translation, which used “semi-liquid” for “semiliquido.” However, the district court found that there were many differences between the priority application and the U.S. application, which suggested that those differences were intentional. Id. at *4.

IBSA also noted that the specification cited internally to pharmaceutical references which used the term “semi-liquid.” But the court concluded that those citations merely established that the applicant knew of the term “semi-liquid” and chose not to use it. Id. at *5. The court further noted that a person of ordinary skill in the art (POSA) would understand from the specification that a “half-liquid” was not a gel or paste, which directly contradicts IBSA’s proposed construction of a substance “having a thick consistency between solid and liquid.”  Id. at *6.

Reviewing the prosecution history, the district court noted that at one point the application had a pending claim using “half-liquid” and another claim, depending from that claim, using the term “semi liquid.” The dependent claim was removed before the patent issued, but the district court seized upon this difference in claim terms used as “evidence that the applicant did not mean ‘semi-liquid’ when he used the term ‘half-liquid.’” Id.

After determining that ISBA’s proposed construction was not supported by the record, the court analyzed whether a POSA would have been able to understand the term “half-liquid” with reasonable certainty. Crediting Teva’s expert’s testimony that the term “half-liquid” was not a well-known term in the art, the district court concluded that the “ambiguity renders it impossible for a POSA to know, with reasonable certainty, whether they are dealing with a half-liquid within the meaning of the claim.” Id. at *7.

Federal Circuit Affirmed the District Court Decision: Applying the Nautilus “reasonable certainty” standard, the Federal Circuit affirmed the district court’s decision.

Turning first to the claims themselves, the Federal Circuit concluded that “the claim language clarifies only that a ‘half-liquid’ differs from a ‘liquid,” but does not make the meaning of “half-liquid” reasonably clear. Id. at *8.

Turning next to the specification, the Federal Circuit agreed with the district court that several passages containing disjunctive lists “designate that a ‘half-liquid’ is an alternative to the other members of the list, including pastes and gels.” Id. at *8. However, because “[p]astes and gels…have a thick consistency between a liquid and a solid and would be included in IBSA’s proposed construction[, s]uch inclusion is at odds with the above passages and creates uncertainty as to the boundaries of a ‘half-liquid.’” Id. at *8-9. Thus, nothing in the specification helped the Federal Circuit clarify the boundaries of “half-liquid.”

With respect to the prosecution history, the Federal Circuit agreed with the district court that the differences between the Italian priority application and the ’390 patent application would indicate to a POSA that the differences were intentional. Id. at *10. The Federal Circuit also determined that the removed dependent claim reciting “semi-liquid” corroborated an intentional difference between using that term and “half-liquid.”

Finally, the Federal Circuit agreed with the district court’s assessment of the extrinsic evidence. Since no scientific dictionary in the record contained the term “half-liquid” and since IBSA’s expert could not explain how a POSA would know what constitutes a “half-liquid,” the Federal Circuit concluded that there was no clear error in the district court’s determination that “the extrinsic evidence does not supply ‘half-liquid’ with a definite meaning….” Id. at *12-13.

Take-Away: Definiteness of claim language must be analyzed not in a vacuum, but in light of (1) the content of the particular application disclosure, (2) the teachings of the prior art, and (3) the claim interpretation that would be given by one possessing the ordinary level of skill in the pertinent art at the time the invention was made. Nautilus, Inc. v. Biosig Instruments, Inc., 134 S.Ct. 2120, 2128 (U.S. June 2, 2014). Practitioners should try to avoid claim language that could raise questions about “reasonable certainty” under 35 U.S.C. §112(b). Undefined terms that do not have well-established meanings in the art, such as “half-liquid” in this decision, are the types of claim language that could raise questions regarding indefiniteness.

In addition, this case stands as a good reminder of the importance of carefully reviewing translations and discussing any uncommon or unusual terminology with the inventors before filing an application with the USPTO.  The additional care spent in conducting such a review could make the difference between a valid claim and one that is deemed indefinite.