updated 04:30 pm EDT, Mon June 20, 2011
Rights only transferred on May 11th
Apple had to obtain the US "AirDrop" trademark for OS X Lion from an Android app marketer, according to Patently Apple. The latter party is Urban Airship, which continues to use the name for a service in which Android developers upload an app, receive redeem codes and distribute them to other people. The trademark was transferred on May 11th, and the change took effect June 9th.
OS X Lion was only fully unveiled on June 6th during Apple's WWDC 2011 keynote. The AirDrop feature lets users quickly share files with other nearby Macs, although they must be within a 30-foot radius. Lion is scheduled to ship sometime in July.
Apple is noted to have also filed for an AirDrop trademark in China. In Canada the company has meanwhile filed for the term "Photo Stream," a reference to the browsing and sync component in iCloud. The submission was made on June 6th, suggesting that Apple didn't want the name publicized until iCloud was formally revealed.