The International Organization for Standardization officially unveiled on Wednesday that Microsoft’s Office Open XML document formats met the necessary number of votes and has been approved as and ISO/IEC International Standard, one day after the media and Microsoft proclaimed the vote as a success, before any official confirmation was given.

Microsoft Corp’s general manager of Interoperability and Standards said one day before the approval was announced: “With 86 percent of voting national bodies supporting ratification, there is an overwhelming support for Open XML. This outcome is a clear win for the customers, technology providers and governments that want to choose the format that best meets their needs and have a voice in the evolution of this widely adopted standard.”

Initially the proposal was rejected in the “fast-track vote” ended September 2007, but re-entered discussion under joint technical committee rules. A ballot resolution meeting (BRM) later held in Geneva on 25-29 February 2008 resulted in a massive withdrawal of previously disapproval votes, which led to the approval of the document as an International Standard.

OOXML, the default file-saving format of Microsoft Office 2007, is actually a rival to an already approved open standard, the Open Document Format (ODF). A lot of experts argue that having two competing similar open standards defeats the purpose of having open formats in the first place, while others say that Microsoft built the format on purpose very complicated so it can't be fully translated into another format.

Robertson added in his Tuesday statement: “The input from technical experts, customers and governments around the world has greatly improved the Open XML specification and will make it even more useful to developers and customers … We are committed to supporting this specification in our products, and we will continue to work with standards bodies, governments and the industry to promote greater interoperability and innovation.”