Apple to Allow Virtualization of Leopard (But only on Apple hardware ) In a notable about-face, Apple has changed its stance with regard to allowing Mac OS X Server to be run inside a virtual machine (VM), much as Parallels Desktop and VMware Fusion make it possible to run Windows and other PC-based operating systems on a Mac. Until the release of Mac OS X 10.5 Leopard Server, Apple's software license agreement explicitly forbade running multiple copies of Mac OS X Server on a single Mac, preventing Parallels and VMware from including Mac OS X Server among the operating systems that could be virtualized legally. Apple's Tiger Server software license agreement reads: This License allows you to install and use one copy of the Mac OS X Server software (the "Mac OS X Server Software") on a single Apple-labeled computer at a time. However, a sharp-eyed systems engineer noticed that Leopard Server's software license agreement is significantly different. Dave Schroeder, Senior Systems Engineer at the University of Wisconsin-Madison, posted to the MacEnterprise.org mailing list about his finding, calling out this change: This License allows you to install and use one copy of the Mac OS X Server software (the "Mac OS X Server Software") on a single Apple-labeled computer. You may also install and use other copies of Mac OS X Server Software on the same Apple-labeled computer, provided that you acquire an individual and valid license from Apple for each of these other copies of Mac OS X Server Software. This change applies only to Leopard Server, not to the desktop version of Leopard. Apple has not changed the software license agreements for either version of Tiger.