Compare
MutuaL is a strong copyleft license with a network clause.
Where it sits
Comparison with other licenses
| License | Copyleft Strength | Network Source | Patent Protection | Anti-DRM | Combines with other FOSS |
|---|---|---|---|---|---|
| MutuaL | Strongest¹ | Yes | Yes | Yes | Yes |
| GPL-3.0 | Strong | No | Yes | Yes | Limited |
| AGPL-3.0 | Strongest | Yes | Yes | Yes | Limited |
| MPL-2.0 | File-level | No | Yes | No | Yes |
MutuaL sits between AGPL (strict copyleft) and MPL (file-level copyleft) in combining strong copyleft with cooperative licensing. Unlike GPL-family licenses, MutuaL is designed to coexist with other free/open licenses without extending its copyleft to components kept in separate files.
¹Scored for the core software. Code that only runs alongside MutuaL software, or talks to it through a documented standard interface, stays separate, and MutuaL does not extend its copyleft to it (see Clarity in the license). AGPL-3.0 is commonly read more broadly for plugins and linked code. That trade is deliberate.
SPDX® Identifier: MutuaL-1.3 (the default) or MutuaL-1.3-only. Pending OSI approval and SPDX inclusion; use the badge and file headers for now.
Identifiers
Put one of these in a file header or a package manifest. The suffix decides whether a later version of the license can apply to your software, and that decision belongs to you, not to the reader.
Upgrades allowed (recommended)
MutuaL-1.3
A later version applies only if it is an official release at the license's home and it adds no restriction that would make you non-compliant.
Locked to this exact version
MutuaL-1.3-only
-only code combines only with code under that same version. Code under different
versions may otherwise combine, with the newest version governing.
Free and open
MutuaL is built to meet the Free Software Definition and the Open Source Definition, and its Cooperation clause names both. Please note that it has not been through either approval process, so this site claims no such approval, and no page here says the license is OSI-approved or FSF-approved.
Key features
- Plain language: Written in everyday English
- Strong-as-it-needs-to-be copyleft: Copies you share, changed or not, and software based on MutuaL stay under MutuaL, so recipients get the same freedoms you did
- Network-aware: Others who use a modified version over a network, or a service that depends on MutuaL for core functionality, must be offered its source
- Cooperative: Combines with other free/open licenses without extending MutuaL's copyleft to parts kept in separate files
- Patent-aware: Includes a patent grant and a clear "no patent attacks" rule. The rule binds only people who accepted the license.
- Anti-DRM/anti-TiVoization: No technical measures that block users from exercising their rights
- Contributor-friendly: Contributions remain part of the commons under the same license
Or, in choosealicense.com terms:
Permissions of this strong-as-it-needs-to-be copyleft license are conditioned on sharing MutuaL-licensed source, under the same license, with recipients and users of a network service that depends on it for core functionality, even if unchanged. License, copyright, and credit notices must be preserved, and no technical measures may stop recipients from exercising their rights. Contributors grant patent rights, and a patent attack on licensees forfeits all rights under the license. Copyleft does not reach other free or open source files combined with it.
We recommend reading the full license text to understand it completely. It is written to be readable for a reason.
Not legal advice
Nothing here is legal advice
This site explains a license and reports what its text says. That is not the same as advice about your situation. If you plan to use MutuaL in a high-stakes or commercial context, consult a qualified lawyer.