Why GPL v2 Frequently Asked Questions

1. What license change is being proposed?

Sun proposes to introduce GPLv2 with Classpath exception for NetBeans software as a second license option along with CDDL. GPL v2 is an open-source license. Please see http://opensource.org/licenses/gpl-license.php for the text of the license.

2. Why does Sun want to dual license NetBeans software under CDDL and GPLv2 with Classpath Exception?

The GPL v2 license will provide an additional option to vendors that are unable to work with NetBeans software under the CDDL license.

Adding GPLv2 as a license option will make NetBeans software even more Linux friendly.

Adding GPLv2 with Classpath exception to NetBeans software will keep product portfolios and bundles consistent. Sun open sourced its JDK implementation under GPLv2 and the GlassFish project is dual-licensed under CDDL and GPLv2 with Classpath exception.

3. What is the Classpath exception?

The Classpath exception was developed by the Free Software Foundation's GNU/Classpath Project (see http://www.gnu.org/software/classpath/license.html). It allows you to link an application available under any license to a library that is part of software licensed under GPL v2, without that application being subject to the GPL's requirement to be itself offered to the public under the GPL.

4. Why is the Classpath exception necessary?

If an application needs to be distributed with parts of NetBeans software under GPL v2, that application could be subject to the requirements of the GPL that all code that is shipped as part of a "work based on the [GPL] program" also be GPL licensed. Accordingly, a GPL license exception is needed that specifically excludes from this licensing requirement any application that links to the GPL implementation. The Classpath exception accomplishes this. This would be, for example, important for module developers, that are always linking with NetBeans APIs, but also for those that build applications on top of the NetBeans Platform.

5. How will adding GPL v2 affect current distributions?

It will not affect current distributions. Current and future distributions will still be available under CDDL. New distributions, starting with the NetBeans 6.0 release, will be available under both CDDL and GPLv2 with Classpath exception.

6. How can something be released under two licenses?

Dual-licensing is the practice of distributing identical software under two (or more) different sets of terms and conditions. When software is dual-licensed, recipients can choose which terms under which they want to obtain the software. The two usual motivations for dual-licensing are business models and license compatibility.

In the case of NetBeans software, we're distributing the code under two licenses, CDDL and GPLv2 with Classpath Exception, for license compatibility. That will allow code from differently licensed free software projects to be combined with NetBeans software, and will give our users the choice to pick a license that they feel more comfortable with. Sun is adding GPLv2 as the option, since as a matter of policy, Sun never takes rights away, so the NetBeans code will continue to be available under the CDDL license.