The VFAT patent isn't FRAND because it was just a de-facto standard that became popular because it was compatible with over 95% of desktop and laptop computers at one point in time.

Of course, you'd think that a convicted monopolist might have some obligations with respect to licensing patents essential to de-facto standards created by the same monopoly power. In today's world, unfortunately, you'd be wrong.

It is all about the dtandards body. I don't know which orgs are responsible for UEFI specs and SD format specs. It's up to the standards body to demand FRAND licensing.

There aren't any international standards that demand a vfat file system, are there? Are the vfat patents still in force, because I haven't payed anyone for those on any of my Linux systems. Is SD an ISO standard or just a consortium standard? (I don't know)

I'm not trying to say Microsoft has the cleanest hands with respect to patents, but in this case, it seems clear cut.