OpenZFS is based on the ZFS file system and logical volume manager created by Sun Microsystems Inc. in 2001 for its Unix-based Solaris operating system. Sun released the source code for ZFS under the Common Development and Distribution License (CDDL) as part of the open-source OpenSolaris operating system. Developers subsequently ported ZFS to additional operating systems, including FreeBSD and many Linux variants.
After acquiring Sun Microsystems in 2010, Oracle Corp. trademarked the name “ZFS” and turned ZFS into its proprietary root file system for Oracle Solaris, Oracle’s ZFS Storage Appliances, mainframe storage (VSM), and other Oracle technologies.
The OpenZFS project formed in September 2013 as the successor to the open-source community that developed ZFS prior to Oracle’s acquisition of Sun. Founding members of the OpenZFS project include Matt Ahrens, one of the chief architects of ZFS while he was an employee of Sun Microsystems.