So, until all (or some large quantity) of software produced by an organization is open source, any software produced by an organization that is open source should not be considered worthwhile efforts?
* Release lots of software with a conditional patent grant: awful.
* Release lots of software with no grant (e.g. BSD): OK.
* Release very little software, and that under the no-grant license (e.g. MS): you rock.
Sorry, but that's completely f-ing backward. It's literally impossible to get to there from open-source principles, so what what principles are people starting from?
It's true that, practically, most companies won't ever have to worry about Facebook infringing their patents, but I think it's garbage on principle to reserve first-strike litigation while making it impossible for someone else to do the same and use software you've made available under a supposedly permissive license.
That phrase alone should swing the "legal risk" argument the other way that how it's being portrayed here.