Some are for sure, but this kind of stuff often requires specialization which may not be in house. Also often you want a second opinion from outside legal counsel.
I’m sure both Apple and Qualcomm have large legal teams experienced in this kind of litigation.
I'm sure those teams often ask for outside help. I know the corporate lawyers I've talked to (mandatory legal training...) have told me about sitting in a trial watching as the outside lawyers he hired for the case did the actual arguments in court.
Both sides employ outside counsel. They're large multinational law firms that charge a high hourly rate (high 3-figures to 4-figures depending on the seniority of the attorneys).
Outside legal also helps remove blinders and bias, somewhat. Yes, you're paying them, but they're also less beholden to "their bosses" as in-house counsel is, and more easily overriden, so it can be a good sanity check as to the merits of a case.
But the outside trial counsel for both firms in the San Diego trial might be smarting a bit for missing out on fees for what would have been a huge trial.