The thing about patent local rules is that they often run contrary to the procedures established in the FRCPs. The FRCPs often work more like a funnel, only gradually narrowing and restricting parties’ ability to change their contentions and positions as the case proceeds. Didn’t get things just right in your pleadings? Need to change a position set out in a rog response? No problem (usually).
Instead, as even the earliest cases interpreting the EDTX patent rules’ predecessor, the ND Cal’s patent local rules stated, and the Federal Circuit later acknowledged, the rules permissibly provide a precise timeline for parties to disclose their infringement, invalidity, and claim construction positions “specifically to require parties to crystallize their theories of the case early in the litigation so as to prevent the shifting sands approach to claim construction.” O2 Micro, 467 F.3d at 1364 or thereabouts. Making changes later usually requires a heightened showing – something FRCP 15 would be horrified at, but which is well within courts’ discretion in managing these complex cases.
Of course that necessarily creates a new form of satellite litigation over the timeliness of proposed changes. The other day I posted on the issue arising in connection with a request to amend invalidity contentions, and this recent order addresses the same question when it comes to claim construction terms and positions.