Prosecution Arguments Distinguishing Prior Art Were Clear Disavowal of Claim Scope

SpeedTrack, Inc. v. Amazon.com, Inc., et al., No. 2020-1573, 2020-1660 (Fed. Cir. June 3, 2021)

The plaintiff sued multiple retailers for infringement of a patent directed to computer filing systems for accessing data according to user-designated criteria. The district court found the applicant had disclaimed prior art hierarchal filing structures. The plaintiff stipulated to noninfringement under this construction and appealed.

The only issue on appeal was whether there was a clear and unmistakable disavowal of predefined field-and-value relationships in the filing system. The prior art disclosed hierarchical field and value systems, for example “Language” as a field and “English” as a value. The applicant had distinguished the prior art as a variation of conventional hierarchal systems, whereas the invention did not require a two-part hierarchical relationship because it was “essentially fieldless,” allowing free-form association of category descriptions. The Federal Circuit agreed that these arguments were a clear disavowal of hierarchal field-and-value relationships.

The Federal Circuit rejected the argument that the applicant had only clarified that the patent claims could cover hierarchal relationships between fields and values (e.g., the value “English” and must relate to the “Language” field) but not between values. The prior art disclosed the same arrangement such that there would be no distinction if the plaintiff were correct. That the applicant had distinguished the prior art on other grounds was also of no import because disclaimer could occur regardless of other prosecution arguments. Finding the remainder of the plaintiff’s arguments unpersuasive, the judgment of noninfringement was affirmed.

Read the full decision here.