In an interview with the Fortune magazine, Microsoft stated that open-source software violates 235 of Microsoft's patents. Lawyer Brad Smith from Microsoft says the Linux kernel violates 42 patents while the user interface and other design parts violate another 65 patents.
Smith further claims that OpenOffice violates 45 Microsoft patents and that another 83 violations were found in other open-source programs.
It is not entirely clear how Microsoft might proceed in enforcing these patents, but the company has been encouraging large tech companies that depend on Linux to ink patent deals, starting with its controversial pact with Novell last November. Microsoft has also cited Linux protection playing a role in recent patent swap deals with Samsung and Fuji Xerox. Microsoft has also had discussions, but not reached a deal with, Red Hat, as noted in the Fortune piece.
Microsoft CEO Steve Ballmer is also quoted in the article as saying Microsoft's open-source competitors need to "play by the same rules as the rest of the business."
"What's fair is fair," Ballmer told Fortune. "We live in a world where we honor, and support the honoring of, intellectual property."