I've never heard the term "invalidity counterclaim" and I was in Google Patent Litigation where suits come in constantly. IPRs were pretty standard. Maybe the lawyers did use it and I just never heard it.
If something was going to trial, then "invalidity" was one of the possible defenses, as was "non-infringement."
Who are you making this claim TO? The court? The PTO?
I've never heard the term "invalidity counterclaim" and I was in Google Patent Litigation where suits come in constantly. IPRs were pretty standard. Maybe the lawyers did use it and I just never heard it.
If something was going to trial, then "invalidity" was one of the possible defenses, as was "non-infringement."
Who are you making this claim TO? The court? The PTO?