All of the sitting judges in the District of Delaware require, in their form scheduling orders, that each party (or each side) may file no more than three motions in limine.
But winning a MIL can really change the scope of trial by precluding key evidence or arguments. In complex patent cases, parties very often want more (sometimes many more) than three MILs to shape the trial in their favor.
One common attempted solution is to merge multiple MILs together. Instead of "exclude late-disclosed doctrine of equivalents theory" and "exclude a late-disclosed exhibit related to copying," a defendant might file a MIL entitled "exclude untimely theories and evidence" that relates to both of those things, …
