CodeWeavers and Microsoft Licensing Questions

The interaction of CodeWeavers' products (CrossOver Linux™, CrossOver Mac™, and CrossOver Server) with those of Microsoft raises legal issues around what Windows software can be run under Wine. In order to help our customers better understand these issues, CodeWeavers has compiled a list of commonly asked questions and their answers.

Q. Can Microsoft sue CodeWeavers or its customers for copyright infringement or reverse engineering, either for Windows or its Windows applications such as Microsoft Office?

A. No. The underlying technology utilized by CodeWeavers to enable Windows software to run under Linux is an open-source technology called Wine. Wine has been developed completely independently, with no reverse engineering and no access to Microsoft source code. The Wine source tree, with a complete revision history since the inception of the project, is freely available to the public, and will substantiate the claim that Wine was created as a strictly separate entity from the Microsoft proprietary code base.

Q. Can Microsoft prevent CodeWeavers' customers from running Microsoft applications on Linux?

A. No. Microsoft's end-user licenses do not preclude operating their applications under other operating systems. Were Microsoft to attempt to prohibit such usage, by requiring that Microsoft products be run only on the Windows OS, they would be in violation of the Sherman Anti-Trust Act. The Sherman Act precludes making the usage of a non-monopoly product dependent on the purchase of a monopoly product. Microsoft has been convicted of monopolist practices under the Sherman Act regarding their operating systems. As a result, they cannot legally make Microsoft Office dependent on having a Windows OS license.

Q. Isn't Wine a risky new technology?

A. No. In fact, Wine has been in active use since 1993. Since then, it has been adopted by many large companies and integrated into their products, including Borland® (Kylix™ development environment), Google® (Picasa), IBM® (WebSphere® Studio HomePage Builder), and AccPac® (Linux versions of ACCPAC Accounting solutions). Wine is a stable, well-understood technology that is being actively refined and enhanced to better support Win32 applications.

Q. Can Microsoft change its Win32 application programming interface (API) and break Wine?

A. No. There is a common misperception that Microsoft changes the Win32 API on a constant basis, thereby making it difficult for Wine to "keep up". In fact, this isn't true at all, since changing the API would break Microsoft's existing codebase for a very large installed base of systems. So long as other software vendors produce or support software for the Windows 98, Windows 2000, and Windows XP platforms, Wine will work as well, since Wine is a competitive replacement for those platforms.