>Unfortunately, exFAT has been adopted by the SD Association as the default file system for SDXC cards larger than 32 GB. In our view, this should never have happened, as it forces anyone who wants to access SDXC cards to get a license from Microsoft, basically making this a field owned by Microsoft.<p>So, this is a bit of a cultural/perception gap between FOSS developers and standards bodies. Most standards bodies have a patent policy of "as long as all the standards-essential patents are licensable for a uniform fee, we're good". Convincing patent holders to not extract royalties from their patents for the sake of easing the lives of FOSS implementers is much, much harder[0].<p>Microsoft isn't even the only SEP holder for SD, and the standard makes no attempt at being a royalty-free standard. In fact, early SD standards were NDA'd[1] and prohibited FOSS implementation <i>at all</i>.<p>[0] In fact, so hard that the EU has a conspiracy theory that Google/AOM bullied a patent holder into doing this<p>[1] Remember, SD cards were basically MMC with primitive DRM