Take an unscientific sample (1 month of CAFC rulings), sum how many times attorneys who prosecuted the application also presented the case in court, and draw nebulous conclusions therefrom (and before the month is over).
In May, there were 13 decisions where the attorneys named on the issued patents could be compared with those listed as counsel of record (in others, the attorney or firm went unnamed on the patent). Also, there was reason to put aside those cases where the litigant was an assignee of the patent/s, since that made it less likely that the prosecuting attorney still had a client relationship with the litigant. In the remaining ten cases, there were three where the same attorneys prosecuted the patent and litigated the infringement case. That the figure was over a quarter of the sample was surprising.
When the District Judge or CAFC is interpreting the claims based on the intrinsic evidence, i.e., the work of the attorney now litigating the patent case, there must be occasions where counsel advocates, but does so based on first-hand knowledge. What did an amendment or argument mean, or what was the applicant’s intent; what happened when the examiner was interviewed; what prior art was known but not disclosed, etc. Seems like a difficult task, and one that involves putting one’s own work between the crosshairs of the lawsuit and the client’s best interests.
In today’s ruling in Cat Tech v. Tubemaster, the CAFC titles a section “Semantic Antics” to describe one claim interpretation argument. Another passage calls a construction argument “strained” to the point that it “renders an important claim limitation …fundamentally meaningless.” Understanding your own wordsmithing is easy, but getting an accused infringer or a court to understand it in the way you had hoped for is less than easy.