Infotech and the Law | Open-source licensing is at the crossroads

Users of open-source general public licenses should be prepared to decide early next year whether to stick with Version 2 of their GPL or opt for GPLv3.

GPL is one of the most well known and widely used open-source licenses. GPLv2 was released in June 1991.

A first draft of GPLv3 was released in January. A second draft, released last month, addresses concerns raised by the first draft. A final version of GPLv3 is expected in early 2007, then GPL users will need to decide, where they have the option, which version is better for them.

Here are some issues to consider when deciding between GPLv2 and GPLv3.

Patents. GPLv2 does not include an express patent license grant to downstream users. GPLv3 requires a covenant not to assert any of your essential patent claims in the GPL-covered work or modifications against downstream users. If you do bring suit, certain of your GPL license rights terminate.

If you have or get certain patent licenses from others, you either must shield downstream users against related infringement claims, or ensure that they can copy the corresponding source code free.

Digital rights management. GPLv3 precludes the use of technological restrictions, such as digital rights management technology, that prevent downstream users from installing or running modified versions of the GPL code. It also requires that you waive certain rights and disclaim any intention to limit operation or modification of a work you distribute.

It further requires that all necessary encryption keys be distributed. GPLv2 has no such restrictions.

License compatibility. A prohibition in GPLv2 on use of other terms prevented the code from being used with certain open-source code. GPLv3 partially addresses this by allowing some additional terms, including certain permissions and requirements.

Permissible additional requirements include terms that relate to reasonable legal notices or author attributions, marking modified versions to distinguish changes from the original version, additional warranty or liability disclaimers, limiting use authors' names or trademarks and other ramifications for initiating patent lawsuits.

Prohibited are additional requirements relating to attorney's fees; choice of law, forum or venue; arbitration; and the requirement that copies be governed by a license other than the GPLv3, among others.

Related entities. GPLv2 was vague with respect to rights when open-source software was transferred to related entities. GPLv3 permits transfers of code from third-party developers or pursuant to transfers in corporate control without constituting a distribution (and the obligations that brings) for purposes of determining rights under GPL.

Shared libraries and dynamic linking. The impact of GPLv2 on dynamically linked software and system libraries that are used with GPLv2 code is not clear. GPLv3 clarifies shared libraries files and dynamically linked subprograms are affected only if the GPLv3 code is designed to require them. It excludes files or libraries that are invoked by the GPLv3 code and that can be readily substituted. This limits the files and libraries that are affected by GPLv3 license requirements as compared with GPLv2.

Charging fees. GPLv3 clarifies that you may charge for any copy of the object code and any support or warranty protection you provide, but severely limits what you may charge for conveying the corresponding source code. And it prohibits imposing royalties or license obligation on downstream users.

Many of these provisions were not specifically addressed in GPLv2 and should be considered before you decide between GPLv2 and GPLv3 code.

James Gatto is a partner in the Intellectual Property Department of Pillsbury Winthrop Shaw Pittman and chairman of the firm's Open Source practice team. He is a frequent author and speaker on open-source issues and is a member of the Intellectual Property Owners Open Source Committee. He can be reached at james.gatto@pillsburylaw.com.