what version is os x mavericks
APSL, BSD, GPL v2, and Apple EULA and NDA. Preceded by. OS X Mavericks (version 10.9) is the tenth major release of OS X (now named macOS), Apple Inc.'s desktop and server operating system for Macintosh computers. OS X Mavericks was announced on June 10, 2013, at WWDC 2013, and was released on October 22, 2013, as a free upgrade through the Mac App Store worldwide.