Challenge
The specification never explained what “arrival-time bounds” meant or how it differed from a conventional ETA, and the patent’s own prosecution history added no clarity. Without a clear claim scope, the plaintiff’s infringement theory was hard to test.
Approach
A double patenting rejection pointed us to the parent application, and we reviewed its 240-page file history. On page 165, the applicant defined bounds as an earliest and a latest arrival time, plus the probability that the arrival falls between them. We applied that definition to the plaintiff’s infringement contentions and found three gaps:
- The accused product showed only a single-point ETA, not bounds.
- The contentions showed no stated confidence interval, such as a 95% or 90% probability.
- The ETA appeared to go to the fleet manager, not back to the same device that provided the location. The applicant relied on that limitation to overcome the prior art, which could limit the plaintiff’s use of the doctrine of equivalents.
Watch How We Found the Page 165 Statement
