Epos Techs. Ltd. v. Dane-Elec S.A., 766 F.3d 1338 (Fed. Cir. Sept. 5, 2014) (HUGHES and Bryson) (D.D.C.: Nickerson) (2 of 5 stars)

Federal Circuit reverses construction of four claim terms and vacates judgment of non-infringement.

Claim Construction: Two patents claimed a transmitter device for digitizing strokes of a handheld “drawing implement” with circuitry that operates the transmitter for a “given time interval” after the system senses there is no longer a downward force on the implement. The term “drawing implement” was not limited to a “conventional” writing utensil. Neither the claim language nor specification excluded non-conventional utensils. “Although it is true that the specifications recite embodiments including ‘conventional’ writing implements, there is no clear indication in the intrinsic record suggesting that the claims are limited to ‘conventional’ drawing implements.” Slip op. at 8. Moreover, the “given time interval” was not limited to a few seconds or less. The patent described embodiments that “typically” or “preferably” involved shorter time intervals but did not exclude longer ones.

A third patent claimed an apparatus with sensors that track the position of a “marking implement.” The “marking implement” was not properly limited to “an implement that has a marker tip (and not a pen tip).” Pens or pencils can also mark surfaces, and the specification interchangeably referred to the “marking implement” as a “pen” and its tip as a “pen tip.”

A fourth patent claimed an apparatus for capturing electronic data from a writing surface that included sensors and a “temporary attachment” for affixing them. The “temporary attachment” did not need to be something that “can be removed” from the apparatus. The claim required the attachment to be part of the apparatus itself, so it was not something that can be removed from it. Moreover, the district court’s construction excluded the preferred embodiments.

Doctrine of Equivalents: A fifth patent involved a drawing implement with a device that transmitted an “intermittent ultrasound signal.” The district court found that a “continuous” signal was not equivalent as a matter of law because it would vitiate the “intermittent” limitation. But it was error to “‘shortcut’ the inquiry by identifying a binary choice (continuous or intermittent) that is not compelled by the ’371 patent and the record evidence.” Slip op. at 17. Instead, the district court should have also considered the “function” of the accused products and the patentee’s expert declaration explaining why they were equivalent before deciding if summary judgment was appropriate.