The study shows that when it comes to software, open-source varieties face fewer patent threats than proprietary ones, Ravicher said. "If one believes the proof is in the pudding, open-source software has much less to worry about from patents than proprietary software." "Consider thisnot a single open-source software program has ever been sued for patent infringement, much less been found to infringe. On the contrary, proprietary software, like Windows, is sued and found guilty of patent infringement quite frequently." These include the patent battle over Eolas Technologies browser technology and the recent settlement between Eastman Kodak Co. and Sun Microsystems Inc. over Kodaks patent being infringed by Java.Ravicher wasnt the only open-source leader to take offense at Ballmers comments."At OSDL, we have a lot of confidence in the robustness of Linux around IP, patents and copyright," said Stuart Cohen, CEO of OSDL (Open Source Development Laboratory), the home organization of Linux creator Linus Torvalds. "Some of the worlds largest vendors share our view and are willing to stand behind Linux to protect their customers, as are we," Cohen said. "HP offers its Linux customers indemnification. So do Red Hat and Novell. Both Novell and IBM have publicly promised to use their extensive patent portfolios to protect Linux customers." Cohen said OSDL has set up a $10 million legal defense fund for Linux customers. "With Linux adoption growing three times faster on the server than any other operating system, customers are clearly not intimidated by FUD and are continuing to embrace Linux," he said. Click here to read about Novells promise to use its patents to protect Linux. Cohen said none of the challengers to Linux has specified where the platform may be overstepping its bounds. "Over the past 18 months, a handful of companies and individuals who are threatened by Linuxs success have tried to argue that Linux may infringe others software patents. We find it interesting that none of those companies or individuals have said which patents Linux may offend. "Yet patents are, by their nature, public; inventions must be disclosed in exchange for the rights granted by the PTO [the U.S. Patent and Trademark Office]. Detractors of Linux on patent grounds should be asked to point to the specific patents that they claim infringe." Check out eWEEK.coms for the latest open-source news, reviews and analysis.