Open Source Licenses Guide & Comparison
Understand at a glance the obligations, contamination risks (copyleft, SaaS), and compatibility of the 11 major licenses with your commercial projects.
Quick Comparison Matrix
| License (SPDX) | Category | Distributed Proprietary Product | SaaS / Cloud Usage | Patent Grant | Detailed Sheet |
|---|---|---|---|---|---|
| MIT MIT |
Permissive | Safe (Allowed) | Safe (Allowed) | Not mentioned | View guide → |
| Apache 2.0 Apache-2.0 |
Permissive | Safe (Allowed) | Safe (Allowed) | Yes (Explicit) | View guide → |
| BSD 3-Clause BSD-3-Clause |
Permissive | Safe (Allowed) | Safe (Allowed) | Not mentioned | View guide → |
| CeCILL-B CeCILL-B |
Permissive | Safe (Allowed) | Safe (Allowed) | Yes (Explicit) | View guide → |
| MPL 2.0 MPL-2.0 |
Weak Copyleft (File) | Conditional (Modified files) | Safe (Allowed) | Yes (Explicit) | View guide → |
| EPL 2.0 EPL-2.0 |
Weak Copyleft (File) | Conditional (Modified files) | Safe (Allowed) | Yes (Explicit) | View guide → |
| LGPL v3 LGPL-3.0-only |
Weak Copyleft (Library) | Dynamic linking only | Safe (Allowed) | Yes (Explicit) | View guide → |
| CeCILL v2.1 CeCILL-2.1 |
Weak Copyleft (Library) | Dynamic linking only | Safe (Allowed) | Yes (Explicit) | View guide → |
| GPL v3 GPL-3.0-only |
Strong Copyleft | Viral risk (Source code required) | Safe (Allowed) | Yes (Explicit) | View guide → |
| AGPL v3 AGPL-3.0-only |
Network Copyleft (SaaS) | Viral risk (Source code required) | Critical SaaS risk (Network disclosure) | Yes (Explicit) | View guide → |
| CeCILL-C CeCILL-C |
Network Copyleft (SaaS) | Viral risk (Source code required) | Critical SaaS risk (Network disclosure) | Yes (Explicit) | View guide → |
Detailed Sheets by License
MIT License
A very short and simple permissive license, focused on maximum freedom for reusers. Ideal for wide adoption.
View guide →Apache License 2.0
A more detailed permissive license than MIT, offering explicit protection against patent litigation. A corporate standard.
View guide →BSD 3-Clause License
Very permissive, similar to MIT, with a non-endorsement clause.
View guide →Licence CeCILL-B (Droit français)
The French equivalent of the MIT/BSD license, compatible with permissive licenses. Governed by French law.
View guide →Mozilla Public License 2.0 (MPL 2.0)
A 'weak copyleft' license that applies at the file level. It requires that changes to MPL-licensed files remain under MPL, but does not affect the rest of the software that uses them.
View guide →Eclipse Public License 2.0 (EPL 2.0)
Ensure that improvements to a component remain open source, without affecting the rest of the project that uses it.
View guide →GNU Lesser General Public License v3 (LGPLv3)
A 'weak copyleft' license designed for libraries. Software using the library does not need to be under LGPL, but changes to the library itself must be shared.
View guide →Licence CeCILL v2.1 (Droit français)
The French equivalent of the LGPL. It is designed for libraries and is governed by French law, while being compatible with the GPL.
View guide →GNU General Public License v3 (GPLv3)
The reference 'strong copyleft' license. Any software that uses a GPLv3 component must be distributed in its entirety under the GPLv3 license.
View guide →GNU Affero General Public License v3 (AGPLv3)
A modified version of GPLv3 that extends the source code sharing obligation to software used over a network (SaaS). It is the strictest copyleft.
View guide →Licence CeCILL-C (Droit français)
The French equivalent of the AGPL, adapted for networked software (SaaS) and governed by French law.
View guide →