OS X Sea Lion

OSX version 10.9, briefly known as "Sea Lion", was introduced as the tenth major release of OS X by Apple Senior VP Craig Federighi on June 10 at the 2013 Worldwide Developers Conference.

Background
Previous releases of Mac OS X and OS X were named after cats and Craig Federighi acknowledged the "dwindling supply" during the WWDC 2013 keynote address. He also concluded that the "out of the box" proposal by the "creative group" of "Sea Lion" would be a "dead end" and announced Apple's intention to begin using California landmarks for at least the next 10 years, beginning with OS X 10.9 “Mavericks”.

Forged packaging
The joke was supposedly lost in translation, and forgeries of OS X Sea Lion reportedly appeared in China.