On an appeal from summary judgment decisions, the U.S. Court of Appeals for the Federal Circuit reversed decisions of non-infringement, unenforceability and indefiniteness, finding that the lower court erred in its claim construction and also failed to consider the relevant time period for purposes of assessing laches. Ultimax Cement Mfg. Corp. v. CTS Cement Mfg. Corp., Case Nos. 08-1218, -1439 (Fed. Cir., Dec. 3, 2009) (Lourie, J).

Ultimax and CTS both produce fast-drying, high-strength cement. Ultimax is the owner of three patents relating to its product. The district court ruled on summary judgment that one of the patents was not infringed and was unenforceable due to laches. It also granted summary judgment that the asserted claim of another patent was indefinite.

In finding the first patent not infringed, the district court, relying primarily on a dictionary definition and testimony of a neutral, court-appointed expert, construed the claim term “soluble CaSO4 anhydride.” It held that the claim term required a compound to include not only calcium sulfate, but also an acid from which water has been removed. This definition was consistent with the ordinary meaning of “anhydride.” The court concluded the specification did not redefine or alter the ordinary meaning of the term “anhydride,” even though it acknowledged one skilled in the art might realize that the drafter intended the claim to refer to “anhydrite” instead of “anhydride,” but went on to note that it could not substitute terms because redrafting patent claims is forbidden even when the failure to substitute terms would lead to a strange result. Because CTS’s cement did not contain an acid from which water had been removed, the district court granted summary judgment of non-infringement.

The district court also held the patent to be unenforceable due to laches because the plaintiffs had waited 12 years after the patent issued to sue. The district court found that Ultimax should have known of CTS’s use of the patented cement at the time the patent issued, citing a long history and affiliation between the owners of the respective companies.

On appeal, the Federal Circuit reversed the claim construction, admonishing the district court for improperly relying only on expert testimony and a single dictionary definition, while refusing to consider other dictionary definitions and “most importantly, the context in which the term was used within the claim and the specification.”

The Federal Circuit also reversed the district court application of laches, noting evidence that Ultimax tried but was unable to gain sufficient access to test CTS’s products to assess infringement, a fact which would not be detectable in the finished product. The Federal Circuit instructed that “the only time relevant to the laches presumption is that after Ultimax knew or should have known of the allegedly infringing product.” Based on evidence that Ultimax could not have assessed infringement outside of the litigation discovery context, the Court concluded there were genuine issues of fact and reversed the district court’s summary judgment ruling.

The Federal Circuit further reversed the summary judgment holding a claim of the second patent indefinite, based on its recitation of a specific chemical formula, which the specification refers to as crystal X and the formula C9S3S3Ca(f cl)2. The district court held this claim term indefinite. First, the court-appointed expert found that the formula for crystal X yielded over 5,000 possible different compounds. Second, the court found that the absence of a comma between “f” and “cl” rendered the claim indefinite for two reasons, notwithstanding that one of ordinary skill in the art would know there should be a comma. The Federal Circuit found that “a claim to a formula containing over 5000 possible combinations is not necessarily ambiguous if it sufficiently notifies the public of the scope of the claims.” With respect to the comma issue, the Federal Circuit held that the district court “erred in declining to view the notation in light of the knowledge of one of ordinary skill.” The Federal Circuit accordingly instructed the lower court to enter summary judgment that the claim is not indefinite.