Tendraes brings us a story about legal experts who are warning that Microsoft's "covenant not to sue" over use of the OOXML specification is both ambiguous and untested. Developers wishing to make use of OOXML are unlikely to understand the complex legal language of the Open Specification Promise, and such a document - being neither a release nor a contract - has never been tested in court. From ZDNet Asia: "David Vaile, executive director of the Cyberspace Law and Policy Center at the University of New South Wales, said that Microsoft participants at a recent symposium on the issue found it challenging to explain how an ordinary person 'or even an ordinary lawyer' could easily determine which parts of the specification were covered. 'This lack of certainty would mean a cautious lawyer may be reluctant to advise any third party to rely on the promise without extensive and potentially quite expensive analysis, and even that could be inconclusive,' Vaile said. 'In turn, this could restrict its viability as a usable standard for less well-resourced users, including small developers and many public organizations.'"