Apple started the suit in mid-2008, when Psystar began selling Mac clones with Apple's Mac OS X operating system running on it. Psystar says what it was doing was perfectly legal. Apple did not agree, and pointed to the Mac OS X end user license agreement which states the OS can only be installed on Apple computers.
Psystar had tried to pass their sales on as "fair use" but Judge Alsup said the company "does not even attempt to address the four factors used to determine fair use."
Additionally, Alsup said Psystar violated the DMCA: "Psystar has violated the DMCA by circumventing Apple's protection barrier and trafficking devices designed for circumvention."
The hearing for whether Apple will receive a permanent injunction or other "remedies" is set for December 14th.
You can read a PDF of the ruling here: Psystar v Apple ruling