Apple does not authorize the use of the Mac OS on any x86 PC other than the ones it has developed itself. The company used technical means (although not the Trusted Platform Module, or TPM, as has been widely mis-reported[22]), to tie Mac OS to the systems it distributed to developers after announcing its switch to Intel's chips.[23]
The Mac OS X EULA forbids installations of Mac OS X on a "non-Apple-branded computer".[3] On July 3, 2008, Apple filed a lawsuit against Psystar Corporation[24] for violating this restriction, among other claims.[25] Apple claimed Psystar "violated the Digital Millennium Copyright Act (DMCA) by dodging copy-protection technologies Apple uses to protect Mac OS X." Apple employs technological protection measures that effectively control access to Apple's copyrighted works. Specifically, Apple charged Psystar with acquiring or creating code that "avoids, bypasses, removes, descrambles, decrypts, deactivates or impairs a technological protection measure without Apple's authority for the purpose of gaining unauthorized access to Apple's copyrighted works."[26] This brief revealed that Apple considers the methods that it uses to prevent Mac OS X from being installed on non-Apple hardware to be protected by the Digital Millennium Copyright Act (DMCA).
On November 13, 2009, the court granted Apple's motion for summary judgment and found Apple's copyrights were violated as well as the DMCA when Psystar installed Apple's operating system on non-Apple computers. A hearing on remedies was set for December 14.[4][27]
On January 14, 2009, the Gadget Lab site of Wired Magazine posted a video tutorial for installing Mac OS X on an MSI Wind netbook, but removed it following a complaint from Apple.[28] Textual instructions remain, but include an EULA violation disclaimer.[29]
On May 15, 2012, the case Apple vs. Psystar Corporation finally ended. The court ruled that Psystar has "violated Apple's exclusive reproduction right, distribution right, and right to create derivative works,"[30] putting an end to the case.