Motions for summary judgment that a particular patent is "not invalid" (why can't we just say valid? I think the patents would like that better) are generally pretty winnable.
A brief survey of the last 10 such decisions found that fully half were granted. Most of those decisions, however, dealt with 112 or 101 issues. If you're moving on your more classic obviousness and anticipation issues, however, you've got a pretty rocky row to hoe. A look back at those opinions finds that only 30% of the last 10 were granted, at least one of which appeared to deal with a defense that was largely abandoned.
Today's opinion in Qorvo, Inc. v. Akoustis Techs., Inc., C.A. No. 21-1417-JPM, D.I. 557 (D. Del. May 2, 2024), is a good example of a situation where such a motion is worth shooting for (and possible ordering higher in your list). The plaintiff, Qorvo (pronounced just like it looks), complained that the defendant's obviousness expert had failed to present any testimony on the motivation to combine. Defendant countered that their expert had done the appropriate analysis, but had simply failed to use various "buzz words" from Graham, KSR, and the like.
Judge McCalla agreed with ...