A US technical standards committee has voted not to approve Microsoft's Office Open XML specification.

The decision by V1, the technical committee that advises the InterNational Committee for Information Technology Standards (INCITS) - US's representive in the ISO, increases the chance that the US will vote against approving Open XML as an open standard.

According to a blog by Rob Weir, an IBM employee who is a member of the V1 committee, Open XML failed to gain the necessary votes - even after multiple motions.

Weir said that the the long-moribund committee had seen an influx of new members in recent months, many of them business partners with Microsoft, such as Mindjet, 3Sharp and Xinnovation. Voting tended to be split, with newer members voting for approval and older members showing less support for the Open XML proposal, also known as DIS 29500, in its current form.

Open XML's approval as a standard is considered key to helping Microsoft maintain its better than 90 percent share among some half-billion productivity software users worldwide. While Open XML - which is built into Office 2007 - is freely licensable by others, Microsoft maintains that it wants to keep the specification separate from the OpenDocument format in order to speed development of new collaboration features and maintain compatibility with old Microsoft Office documents.

V1 members were charged with evaluating Open XML on its technological merits. "This is not supposed to be about whether Microsoft is a monster or if OOXML is bad for your kids," said one committee member who declined to be identified. "It's supposed to be: Is this a spec that ISO can be proud of? From a technical point of view, the answer is yes."

Sun Microsystems, largely considered an avowed opponent of Open XML because of its own development and support for the competing, ODF-based StarOffice suite, found itself in the unexpected position of stating its support for ratifying Open XML -- albeit after some changes in the proposal are made.

"We wish to make it completely clear that we support DIS 29500 becoming an ISO Standard and are in complete agreement with its stated purposes of enabling interoperability among different implementations and providing interoperable access to the legacy of Microsoft Office documents," Jon Bosak, a Sun representative to V1, wrote in an email to other committee members over the weekend. "Sun voted No on Approval because it is our expert finding, based on the analysis so far accomplished in V1, that DIS 29500 as presently written is technically incapable of achieving those goals, not because we disagree with the goals or are opposed to an ISO Standard that would enable them."

"There was no dissension that OOXML should eventually become an ISO standard," said Lynne Price, an XML technology consultant. However, the "weird" and "not well-written" rules created confusion, especially among newer members less familiar with the standards process, she said.

In March, the ISO agreed to put Open XML on a fast-track approval process that will see a vote by ISO's 157 member nations. That's despite lingering opposition by representatives from a number of countries who argue that the Open XML proposal conflicts and overlaps with a previously established standard - ODF - and is poorly written and technically unsound.

INCITS's Technical Advisory Group (TAG) will choose the US position on Open XML's approval, but it did not submit a comment or contradiction on the US's behalf.

Patrick Durusau, chairman of the V1 committee, and Jennifer Garner, administrator for INCITS's technical advisory group overseeing the US position on Open XML, did not immediately return requests for comments.

The revelation comes in the last week that the public can send comments to the Massachusetts over its decision to reverse course and endorse Open XML as an open standard fit for governmental use.

Opponents to Open XML have been urging members of the public to send comments to the commonwealth.

According to Andy Updegrove, a Boston lawyer who maintains the ConsortiumInfo.org blog, only 50 comments had been posted as of late last week.