The US Department of Defense clarified its stance on open source software, saying it is equal to commercial software in almost all cases, and by law should be considered by the agency when making technology purchase decisions.

The memo was not a policy statement but instead a clarification and guidance on the use of open source software (OSS) within the agency. It was issued by David Wennergren, deputy CIO of the department.

In terms of guidance, the memo said OSS meets the definition of "commercial computer software" and that executive agencies are required to include open source when evaluating software that meets their computing needs.

In addition, the memo lays out a list of open source positives, including broad peer review that helps eliminate defects, modification rights that help speed changes when needed, a reduction in the reliance on proprietary vendors, a licensing model that facilitates quick provisioning, cost reduction in some cases, reduction in maintenance and ownership costs, and favorable characteristics for rapid prototyping and experimentation.

"I would consider this a milestone day," said John Scott, director of open source software and open integration for Mercury Federal Systems, a technology consultancy to the US government. Scott helped write some of the open source guidance contained in the memo, which took about 18 months to draft. "The [2003] policy study was OK to use, but this one goes a bit further in expanding on what open source is and why you would want to use it. But it is not just about usage, it is also about helping create [OSS] by submitting changes back out to the public."

Scott says he believes this is the first time guidance has been issued about sharing the government’s own open source changes with the public.

The memo, an update to a 2003 DoD open source directive, clarified the use of sharing code saying there is a misconception within the agency that modifications must be released to the public.

"In contrast, many open source licences permit the user to modify OSS for internal use without being obligated to distribute source code to the public," the memo says. It goes on to advise users to understand distribution requirements for open source licences and mentions the GNU General Public Licence and its specific distribution rules.

On the other hand, the DoD says code fixes and enhancements developed for the government should be released to the public, but only under certain conditions, such as the absence of export or other federal restrictions.

The memo also makes a distinction between freeware and open source software, which previously was the source of confusion and debate within the agency, Scott said.

The DoD already has open source running as part of classified and unclassified systems. In fact, Scott says from one third to one half of the software used inside the DoD is open source. The memo defines OSS as "software for which the human readable source code is available for use, study, reuse, modification, enhancement, and redistribution by the users of that software."

The DoD memo comes on the heels of the Obama Administration selecting Drupal to power its website.