Patent lawyers agrees with my belief that Red Hat will have paid

Many such disputes happen, and there are well-known patterns. I've been following that type of activity for some time, and Patrick Anderson, whose tweets I quoted, is a lawyer focused on patents in the state of Texas, which as you know is an extremely popular venue for such litigation.

In my opinion, by far and away the most probable assumption is that you (Red Hat) have just suffered a Novellization at the hands of Acacia. Patent owners don't grant GPL-style patent licenses protecting all downstream users including non-customers and forkers, unless they're in an incredibly weak legal position (which is doubtful given that the patent wasn't on the verge of invalidation, but on the contrary had proved defensible) *and* tight on cash (which isn't the case with Acacia).

It would be up to Red Hat to put the facts on the table. Can you assure all non-customers using your code on GPL terms that you've covered them? Including all forkers of your code on GPL terms, no matter what kind of GPL-based software they may create?

I'm sure that if you could, you would say so, as you did in a past case.

But you don't, which is weak, and the facts I described above speak a clear language.

Prove that you aren't another Novell, please.