jm ú@]p§²¾ãïÉ"3Hài\A.iªêsTÎkVÕ]L¶I think it is something like shared signature/key all over the place for all shares, and there's an individual key for each account, team, device, folder, etc. for granular security.
https://whatsonchain.com/tx/3c381ba2eaed0be1a2033e3855e78e24cf1be1837f6abfd2cf17ddcb5359533f