The Federal Circuit has again highlighted the importance of prosecution history for patent claim interpretation. In Baker v. Microsoft Corp., No. 2017-2357 (Fed. Cir. Apr. 9, 2018) the Federal Circuit upheld a district court claim interpretation and grant of summary judgement of non-infringement of US Patent 5,486,001.
Defendant Microsoft manufactures and sells various computing devices, peripheral devices, and software. For example, Microsoft sold a computer system that included a camera as a peripheral device.
Plaintiff Baker owns the ‘001 patent. The ‘001 patent is directed towards a “Personalized Instructional Aid.” The ‘001 patent describes a system designed to provide feedback to a user regarding their body movement, e.g., the way the user swings a golf club. The system captures image signals of user movements at one location, compares the image signals with prestored image signals and generates instruction signals based on the comparison at a second “remote” location, and transmits the instruction signal to the first location for display.
Baker amended the claims of the ‘001 patent during prosecution to include limitations directed to performing the method steps at various locations. Exemplary claim 1 of the ‘001 patent recites:
A method for providing an instructional aid for assisting a person to emulate a preferred movement, said method comprising:
capturing and storing initial visual image signals representative of a particular movement at a first location,
storing preferred image signals representative of a selected preferred movement at a second location remote from said first location in a data base of a computer,
transmitting said captured and stored visual image signals from said first location to said computer at said second location,
comparing said captured and stored image signals with stored preferred image signals in said data base of said computer,
regenerating further visual secondary image signals based on said initial image signals of said particular movement adjusted to emulate said stored preferred image signals of said selected movement in said computer, and
transmitting said regenerated signals from said computer at said remote second location to said first location and stored in image presentation means which permits viewing thereof with dialogue relating to said regenerated visual secondary image signals.
(underlined portions of the above claim were added during prosecution)
Baker supplemented the amendments with an argument that “[n]owhere in [the prior art] is there a teaching that the computer system is located remotely from the teaching station as is emphasized in [Baker’s] disclosure,” and that “[t]ransmittance to a separate location for analysis and feedback is critical in [Baker’s] invention, because the programming can be efficiently performed at the remote computer station.” The ‘001 patent was issued based on the amendments and remarks.
Baker sued Microsoft for infringement of the ‘001 patent with its computer and camera system. The computer and the camera of the Microsoft system were used in a same room. Baker alleged that the camera performed the recited method steps at the first location and the computer performed the method steps at the remote second location because they were separate devices, even though they were in the same room.
During claim construction, the district court found that the term “remote” in the claims required “more than physical separation at the same location.” The court pointed to two separate lines of reasoning to support its finding. First, the court pointed to the specification which describes components at the first location as being “discrete” or “one in the same.” The court reasoned that “discrete” could not mean the same thing as “remote,” i.e., remote had to require more than just physical separation. Second, the court held that prosecution history estoppel prevented the interpretation of remote argued by Baker. He had disavowed an interpretation of “remote” as being at a single location when he amended the claims and with the statements made during prosecution accompanying the amendments.
The district court granted summary judgement of non-infringement because the construction of “remote” required performance of the various method steps at locations that were more than merely physically separated at the same location, and the accused products performed the steps at a same location. The Federal Circuit agreed with the district court’s reasoning and affirmed its claim construction and grant of summary judgement.
Lessons for Practice
Key to this case was the court’s reliance on the amendments to the claims and the remarks made to distinguish the amended claims from the prior art. Accordingly, such considerations that may arise during litigation of a patent should be kept in mind during prosecution, especially in the case when arguing features that distinguish from the prior art, but may not be explicitly be claimed. For example, when remarks accompanying an amendment describe the amendment as being narrower than a broadest reasonable interpretation.