Trademark was filed back in the April of 2011.
While Apple has already moved onto OS X "Mountain Lion," the U.S. Patent and Trademark Office has approved Apple's "Lion" trademark.
The U.S. Office of Patents and Trademarks has approved the Cupertino company's trademark after over a year of waiting, with Apple now the legal rights owner to the name for its "computer operating system and application development tool software." The trademark itself is spelled with a capital "L", which is followed by lowercase letters.
A few months before it filed for "OS X MOUNTAIN LION" and "MOUNTAIN LION," Apple filed the request for "Lion" on April 6, 2011. The two former trademarks, however, have yet to be approved.
Apple is no stranger to protecting its trademarks in the past. The firm filed a lawsuit against Amazon last year over the term "App Store," a trademark that the former registered following the release of its iPhone 3G.
The company was also embroiled in a lengthy battle against Apple Corps, who is the Beatles' holding company and owner of the band's record label, over trademark issues, which was settled last week.

*waits for apple to sue me*
If I now write "Lion" (obviously the capital "L" is THE important thing here) ... and it in some way features in my product (I can think of Lion Cereal, google it), then Apple can now sue me???
or is this limited to software? computers? http://www.lion.com/Home are those guys gonna get it from Apple now? please tell me that's NOT true...
*waits for apple to sue me*
Most likely the Lion is only trademarked for IT related products by Apple. It is possible to have a trademark to be used by different industry without violating other same name trademark.
Example: Dove - Shower Gel and Dove chocolate. Both are from different industry but using the same name. They are trademarked under different category by 2 different company.
It is possible for Apple to trademark the word Lion across industries. Another thing to note, the trademark for Lion is only valid in US unless they do the same in other countries.
Burger King is already trademarked by some other guys in Australia, so they couldn't use that name, and instead known as 'Hungry Jack' there.
I honestly had no idea!
Don't doubt Apple, they have sued more than one company already for having an apple in their logo (that don't even look like Apples logo) and they weren't anywhere near the same industries as Apple.
...although, the lions would probably have to declare bankruptcy before they can start nomming -.-
and thanks for clarifying how this is just an IT trademark. does make more sense.
I don't see how anyone can trademark something that is a name of something living, because you are infringing on that living things rights.
Wake up people. They are just as evil murdering companies who want to evolve the world by throwing them into a furnace or lawsuits.
All HEIL apple they say.
I would agree if Apple tried to patent 'Application Store,' but I actually agree Apple can have 'App Store.' (As I recall, Apple was the first to use the term, and 'App' isn't/wasn't actually a word. It was after Iphone everyone started acting hip saying apps instead of application for mobile phones. Correct me if I'm wrong.)
On-topic: Microsoft have 'Windows' for it's OS. Can't really complain Apple getting 'Lion.'
Kids got a little confused since they insists have seen these animal before with different names.