Though untested, many think the BSD and similar licenses provide an implicit grant that can't be strategically revoked. Future case law to the contrary would ma

Though untested, many think the BSD and similar licenses provide an implicit grant that can't be strategically revoked. Future case law to the contrary would make a lot of open software unusable or at least a legal minefield. Providing an explicit grant with explicit conditions of termination makes it easy for Facebook to selectively restrict use of anything that might be under patent in ANY of their projects. At best it's not in the spirit of FOSS and at worst it asymmetrically weaponizes open licenses. 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.