Common Sense Prevails Over Theoretical Patent Claim Construction

A recent Federal Circuit patent decision illustrates the rule that common sense will trump a good theoretical argument, and that litigators must always test their arguments against common sense. In particular, the court held that one of ordinary skill in the art would reject defendant's proposed claim construction because it would not provide the tight fit for orthopedic implants described as necessary to the invention. Howmedica Osteonics Corp. v. Tranquil Prospects, No. 04-1302, (3/28/05).

In Howmedica Osteonics Corp. v. Tranquil Prospects, No. 04-1302, (3/28/05), the Federal Circuit reversed the district court's holding that a patent was invalid under U. S. C. § 112, paragraph 2 because the term "transverse sectional dimensions" was indefinite. Under section 112, paragraph 2, patent claims must “particularly point[] out and distinctly claim[] the subject matter which the applicant regards as his invention.” 35 U.S.C. § 112, para. 2 (1982). Defendants had argued that the term was ambiguous because the term could refer to one-dimensional rather than two-dimensional dimensions.


The court noted that definiteness is a question of law, and it is determined at the time of filing in light of the understanding of one of ordinary skill in the art. The court held that the term could be understood by one of ordinary skill in the art because of extensive references in the specification to the need for a tight fit. Defendant's claimed alternate construction resulted in a loose fit, meaning that it was not a reasonable understanding of the term. The court stated: "These extensive references clarify that the invention requires a very tight fit for the prosthesis. Given the choice between a construction of transverse sectional dimensions that would require a relatively loose fit and a construction that would require a much tighter fit, the record shows that one of skill in the art would readily understand and adopt the latter."