"On the other, it has continued to seek payments for patents it holds that are found in open source technologies and in general uphold its proprietary intellectual property licensing strategy — the opposite of the philosophy behind open source. Microsoft has long held patent-infringement and possible litigation over the heads of open source vendors, at one time claiming that Linux infringed on more than 230 of its patents."
Source: http://www.itworld.com/open-source/66652/has-microsoft-lost-its-war-open-source


