GPL-3.0 License Generator

The GPL v3 License explained

The GNU General Public License version 3 (GPL v3) was released in June 2007 by the Free Software Foundation, drafted by Richard Stallman and lawyer Eben Moglen after a two-year public consultation. It is the canonical example of a strong copyleft license: any derivative work — whether you modified one function or rewrote half the codebase — must itself be released under GPL v3 when distributed.

It grants the freedoms to use, study, modify and distribute the software. In exchange, distributors must (1) make the complete corresponding source code available, (2) license the whole derivative under GPL v3, (3) preserve copyright and license notices, and (4) accept the license's explicit patent grant from every contributor.

What's new in v3 vs v2

GPL v3 closed three big loopholes left open by GPL v2:

• Anti-tivoization — if you ship GPL v3 code on a consumer device, users must be able to install modified versions. This was a direct response to TiVo, which had complied with GPL v2 by releasing source but locked the device with signed bootloaders.
• DRM clause — distributors cannot use technical measures to prevent users from exercising their rights.
• Patent retaliation — explicit, modern patent grant plus a defensive termination provision similar to Apache 2.0.

GPL v3 vs AGPL v3 vs LGPL

• AGPL v3 closes the SaaS loophole: if you let the public interact with the software over a network, you must publish the source. Choose AGPL for hosted services.
• LGPL ("Lesser") allows libraries to be linked by proprietary applications without forcing the whole app to become GPL. Choose LGPL for runtime libraries.
• GPL v3 is the right choice for distributed end-user software (desktop apps, system tools).

Compatibility and famous users

GPL v3 is compatible with MIT, BSD, ISC and Apache 2.0 — any of these can be merged into a GPL v3 project, but the combined work is licensed as GPL v3. It is incompatible with GPL v2-only projects (which is why the Linux kernel, GPL v2 only, cannot absorb GPL v3 code) and incompatible with MPL without dual-licensing. Famous projects: WordPress ("GPL v2 or later"), GIMP, Inkscape, Blender, GCC. The Linux kernel itself remains GPL v2 only.

FAQ

Can I sell GPL v3 software? Yes. GPL allows commercial sale, paid support and dual-licensing. What you cannot do is restrict users from redistributing.

Can someone make a closed-source fork of my GPL v3 project? No — that is the entire point of strong copyleft. Any distributed derivative must be GPL v3 with source available.

AGPL v3 or GPL v3 for my project? Choose AGPL v3 if your software will likely be deployed as a SaaS (network service); choose GPL v3 for software users install locally.

Is the anti-tivoization clause a problem for embedded products? It can be. Manufacturers shipping GPL v3 firmware must provide the keys or means to install modified versions on consumer devices. Many embedded vendors avoid GPL v3 entirely for this reason and prefer GPL v2, Apache 2.0 or MIT.

Famous enforcement case? Cisco/Linksys (2003-2008) was sued by the FSF for distributing Linux-based routers without complying with GPL v2. The case settled with full source release and the appointment of a free-software compliance officer — a precedent that shaped how GPL is enforced today.

Disclaimer. This generator produces a license template — it is not legal advice. Copyleft has business and technical implications; for commercial products consult an attorney.