Others, like Dan Ravicher, the executive director of the Public Patent Foundation in New York, go even further and suggest that those in the free-software and open-source communities need not comply with the license, as it is questionable whether Microsoft actually has any rights for which people would need a license.

"If they do have rights and a license is needed, then the term in the license to Microsoft's rights that requires attribution by the licensee of all of its downstream licenses is in fact not compatible with the GPL, just like the original BSD license, which required a similar attribution, is not GPL-compliant," he told eWEEK.

"However, we should not presume that Microsoft has any valid rights here. They might like to give that impression, but it is not clear. If they don't have any rights, then no one needs a license from them, so whatever terms such a license may contain are irrelevant, because no one needs to abide by them," he said.

The beginning of the patent license where this requirement is set forth states that "Microsoft may have patents and/or patent applications that are necessary for you to license in order to make, sell or distribute software programs that read or write files that comply with the Microsoft specifications for the Office Schemas," Ravicher said.

"If they had any applicable patents, they'd most assuredly tell people what those patents are. I can't see that they have done that. So, all they've said is that they may have patents and, if they do, these are the terms under which they'll license them to you. While it is true the terms of such a license are GPL-incompatible, there is no need to comply with them until we are certain they have something that must be licensed," he said. Others, like Iyer Venkatesan, the product line manager in Sun Microsystems Inc.'s client systems group, said they feel that it remains to be seen whether Microsoft's decision to make its Office Open XML Formats available is a good move or not.

"Customers and partners may meet the new file formats with resistance or skepticism, since Microsoft's XML file format is not compliant with the OASIS [ Organization for the Advancement of Structured Information Standards] OpenDocument file format, which is the industry-standard XML file format," Venkatesan said.

Asked whether the move would make it easier for Sun's office competitor, StarOffice, to interoperate with Office in the future, Venkatesan said it would. "XML in general is much easier to import and export than Microsoft's previous binary file formats. But Microsoft's XML file format is still very closely related to their Office applications and, as a result, they did not design their XML file format to be vendor-independent. It could still be difficult for other vendors to adopt the Microsoft format," he said.

Also, unlike an openly developed file format like the OASIS OpenDocument format, Microsoft could change the format without other parties being aware of the change until Microsoft released the next version of its product.

While StarOffice will continue to support any new Office file formats, "We would prefer to see Microsoft adopt the open and broadly supported OASIS OpenDocument standard, which has been endorsed and supported by companies like Sun, IBM, Novell, Red Hat, Adobe, KOffice and AbiWord," Venkatesan said.

This article was originally published on eWEEK.com.