Reuters reports
that Apple sued "unnamed individuals" on December 13 over a recent
product leak. Additional unnamed parties may be added to the suit once
their identity is known, says Reuters.

While Reuters notes flash iPod rumors have spread through the Web and
some sites have speculated that Motorola-Apple phone stories could be
behind the suit, it seems more likely that the more credible story of a
new Apple audio interface may be the subject of the suit.

This isn't the first time Apple has sought to protect industrial
secrets. Apple sued a contractor in 2002 over leaked Power Mac G5
images and notoriously blocked press passes for so-called "rumor sites"
at Macworld Expo (some of which were surprised at the time to fit in
this category, as the likes of Forbes and Wired have often taken part
in idle speculation)

[Updated: Apple has subpoenaed sites specifically over Asteroid, obviously suggesting the rumor sites had accurate leaked information.]