This is exactly why I posted in a previous thread that OSS projects and even public domain stuff need to patent their ass off. They should collect it into nonprofits that defend OSS institutions. Aside from self-defense, the main reason to patent all this stuff is so the big companies can't. This example shows they will do it any opportunity they can for anti-competitive purposes.
I have no idea. I'd start with organizations like FSF and Apache plus companies that benefit from OSS like Red Hat. Any key, differentiating innovations in their projects or dependencies would be up for patenting. Then, reviewers would look at the strategic importance of the techs to prioritize them. Then, they'd patent as many as their budget allows.