From CNET News:
Apple Computer filed suit this week against three developers it says posted a prerelease version of Mac OS X onto the Internet.
The lawsuit, filed Monday in federal court in San Jose, Calif., alleges that the three men posted a developer release of Mac OS X Tiger onto sites used by the BitTorrent file-trading network. Apple is seeking an injunction to prevent further releases of its software as well as unspecified monetary damages.
In the suit, Apple said the tracker on one of the BitTorrent sites indicated that more than 2,500 copies of one Tiger version were downloaded. The postings began in late October and continued through this month, the Mac maker said.