Summary judgment of noninfringement was improper because of the district court’s erroneous claim constructions.

The patentee owns six patents covering devices that digitize writing utensils and writing surfaces such that writing can be digitally captured. The alleged infringer sought a declaratory judgment that it did not infringe four of the patents. In its answer and counterclaims, the patentee asserted infringement of the two other patents, for a total of six patents-in-suit. The alleged infringer moved for summary judgment of invalidity and noninfringement after claim construction. The district court, analyzing the motion in light of its recent claim construction rulings, granted the motion on noninfringement. The patentee appealed.

The Federal Circuit vacated several claim construction rulings, reversed the grant of summary judgment, and remanded the case. The court found that the district court erred during claim construction. First, the district court wrongly construed the term “drawing implement,” which was present in two of the patents-in-suit, as a “conventional” utensil. It also found that the “pen refills” in the alleged infringer’s product were not “conventional,” and thus granted summary judgment. The court found no evidence in the intrinsic record to suggest the patents-in-suit claimed only “conventional” utensils, and vacated the construction for that reason. The court also stated that whether the alleged infringer’s product used a “drawing implement” as properly construed was a question of fact for the jury, and thus reversed the grant of summary judgment.

The court also vacated other claim construction rulings, including on the terms “given time interval,” “marking implement,” and “temporary attachment.” For each term, the court held that the district court incorrectly read limitations into the claim term that were not present in the intrinsic record. Further, in the case of the term “temporary attachment,” the court held that the district court’s construction read out the preferred embodiments, and was therefore presumptively incorrect absent “highly persuasive evidentiary support.” The court reversed the grant of summary judgment on the patents-in-suit containing these terms.

Finally, the court vacated the district court’s finding of noninfringement under the doctrine of equivalents on one patent. The patent claimed the usage of “intermittent” ultrasound signals. Because the alleged infringer’s product used “continuous” ultrasound, the district court found that it was not equivalent and granted summary judgment of noninfringement. The Federal Circuit stated that the lower court “shortcut” the analysis and should have determined whether a reasonable jury could believe that the use of ultrasound was equivalent.

A copy of the opinion can be found here.