Standardization of Office Open XML

The Office Open XML file formats were standardised between December 2006 and November 2008, first by the Ecma International consortium (where they became ECMA-376), and subsequently, after a contentious standardization process, by the ISO/IEC's Joint Technical Committee 1 (where they became ISO/IEC 29500:2008).

More than a year after being asked by the European Union to standardize their Office 2003 XML formats, Microsoft submitted 2,000 pages of documentation for a new file format to the Ecma International consortium for it to be made into an open standard. Ecma formed in December 2005 a technical committee (TC45) in order to produce and maintain a "formal standard for office productivity applications that is fully compatible with the Office Open XML Formats, submitted by Microsoft". The technical committee was chaired by two Microsoft employees and included members drawn from Apple, Canon, Intel, NextPage, Novell, Pioneer, Statoil ASA, Toshiba, The United States Library of Congress, The British Library and the Gnome Foundation.

During standardisation within Ecma the specification grew to approximately 6,000 pages. It was approved as an Ecma standard (ECMA-376) on December 7, 2006. The standard can be downloaded from Ecma free of charge.

Using their entitlement as an ISO/IEC JTC 1 external Category A liaison, Ecma International submitted ECMA-376 to the JTC 1 fast track standardization process. To meet the requirements of this process, they submitted the documents "Explanatory report on Office Open XML Standard (Ecma-376) submitted to JTC 1 for fast-track" and "Licensing conditions that Microsoft offers for Office Open XML". ISO and IEC classified the specification as DIS 29500 (Draft International Standard 29500) Information technology – Office Open XML file formats.

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