The Commonwealth of Massachusetts, a pioneer in state-backed efforts to support the Open Document Format (ODF) standard, has reversed course and decided to support Microsoft's Office Open XML (OOXML) format in addition to ODF and Adobe's PDF.

In August of 2005, Massachusetts announcedit would require government users to migrate away from closed document formats to open standards. At that time, it considered that PDF and ODF met the requirements of an open standard, but Microsoft's document formats did not.

Proponents of open formats welcomed this move at the time, arguing that only through competition could document interoperability and accessibility be ensured.

ODF backers argue that the format is better suited for keeping documents accessible over the long term, since it is simple and has been developed in an open community. The format also enables competition among different productivity programs, since it's supported by multiple applications - though Microsoft Office only supports ODF via an add-on.

ODF is backed by large companies such as IBM and Sun.

The state's Information Technology Division (ITD) made the change in the latest revision of the state's Enterprise Technical Reference Model (ETRM), posted on the state's website on Monday.

Microsoft said the state's decision was positive and would give users the ability to choose the open file format most suitable for their needs.

Andy Updegrove, a partner with Boston law firm Gesmer Updegrove and editor of the ConsortiumInfo.org Standards Blog, said Massachusetts' move was a serious setback for document format competition.

He said the backing of large buyers such as government bodies is needed if ODF is to become widely used and develop into a serious competitor to Microsoft's OOXML, also known as Ecma 376.

"If no one is competing with Microsoft, then no one will care whether Microsoft contributes new features to Ecma or maintains them as proprietary extensions of Ecma 376, or whether it fully implements Ecma 376, or whether, in fact, it continues to support Ecma 376 at all," Updegrove wrote in the ConsortiumInfo.org blog on Monday. "And then we will be right back where we started - dependent upon a single vendor, and with the accessibility of its all current documents, and indeed the history of our civilisation, at risk."

Many archivists dispute that open standards are better for document preservation, with some favouring the approach of simulating contemporary technology and software in order to maintain document accessibility.

Updegrove said state representatives, including Massachusetts' governor, have been under heavy pressure from Microsoft to change the state's position.

"Here, as in the states where legislation was introduced, the point was forcefully and repeatedly made that Microsoft is the kind of company that can provide jobs and other economic support where and as it pleases," Updegrove wrote.

Andy Oram, an editor at O'Reilly Media, said in an opinion piece on the company's website that the decision would reinforce users' dependence on Microsoft Office.

"It’s not in the public interest for a lightweight, publicly developed standard with multiple alternative implementations to be driven out by a monster of a specification (6,000 pages) that has legal encumbrances and other complexities that mean it can be implemented by only one vendor," Oram wrote.