the NFSv4 ACL Standard is tangentially related to NFS, the TL;DR is that it replicates the kind of ACLs you can create under Windows (ie, seperate "Write to File" and "Append to File" into different permission bits, make inheritance configurable, etc.).
The TrueNAS people (ixsystems) have a patch to bring it to Linux and ZFS; though from what I've heard upstream LKML lists aren't too enthused since they'd rather see this being used by an in-kernel filesystem.