Software License Compatibility Checker
Check whether code under one licence can be used in a project under another, for commercial, SaaS, proprietary, modification and distribution scenarios. Free, no registration.
Using MPL-2.0-licensed code in a proprietary project
Compatible With Conditions
Using MPL-2.0-licensed code in a proprietary project is generally possible if the listed conditions are met.
Confidence: high
Compatibility is directional: using License A code in a License B project is a different question from using License B code in a License A project. Check the reverse direction.
Commercial Use
No issueMPL-2.0 permits commercial use. Commercial use, including selling copies, is allowed; the copyleft conditions still apply to how the code is distributed.
Modification
No issueThe scenario does not include modifying the component. Modification under MPL-2.0: permitted.
Distribution
No issueMPL-2.0 permits distribution subject to its copyleft conditions.
Source Disclosure
ConditionsMPL-2.0 is file-level copyleft: its files must remain under MPL-2.0 and their source must be made available when distributed. Your own separate files in the larger work may use other terms, including proprietary terms.
Attribution
ObligationsMPL-2.0 requires the copyright and licence notices to be kept with copies you distribute.
Patent Considerations
No issueMPL-2.0 includes an express patent licence from contributors. That patent licence terminates for anyone who initiates patent litigation alleging that the work infringes a patent.
Copyleft
ConditionsMPL-2.0 is file-level copyleft: its files must remain under MPL-2.0 and their source must be made available when distributed. Your own separate files in the larger work may use other terms, including proprietary terms.
SaaS / Network Use
No issueThe scenario does not include offering the software over a network. MPL-2.0 has no network-use clause.
Proprietary Use
ConditionsMPL-2.0 is file-level copyleft: its files must remain under MPL-2.0 and their source must be made available when distributed. Your own separate files in the larger work may use other terms, including proprietary terms.
Why?
- MPL-2.0 is file-level copyleft: its files must remain under MPL-2.0 and their source must be made available when distributed. Your own separate files in the larger work may use other terms, including proprietary terms.
- MPL-2.0 permits commercial use. Commercial use, including selling copies, is allowed; the copyleft conditions still apply to how the code is distributed.
- When the obligation applies, MPL-2.0 requires making available the licensed files and your modifications to them.
- MPL-2.0 requires the copyright and licence notices to be kept with copies you distribute.
- MPL-2.0 permits distribution subject to its copyleft conditions.
- MPL-2.0 includes an express patent licence from contributors. That patent licence terminates for anyone who initiates patent litigation alleging that the work infringes a patent.
What do I need to do?
- Make the source of MPL-2.0-covered files (and modifications to them) available under MPL-2.0.
- Keep MPL-2.0 notices in covered files.
- Include the MPL-2.0 copyright notice and licence text with the distributed software (source, binary documentation or an "open-source notices" screen).
Risks
- Initiating patent litigation over the MPL-2.0 work ends your patent licence for it.
Authoritative Sources
Rules applied
MPL_FILE_LEVEL_COPYLEFT (CONDITION), MPL_COMMERCIAL_USE (INFO), MPL_SOURCE_DISCLOSURE (INFO), MPL_ATTRIBUTION (INFO), MPL_DISTRIBUTION (INFO), MPL_PATENT_NOTICE (INFO)
This tool provides general software licensing information and is not legal advice. License obligations may depend on how software components are combined, modified, distributed and used.
How the checker works
Results come from a deterministic rule engine, not from AI. Each supported licence is described by structured facts taken from SPDX, the Open Source Initiative, the GNU Project and the licence stewards: copyleft strength, source-disclosure scope, attribution, patent and network-use terms. Rules combine those facts with your scenario, and every rule that fires is listed with its identifier.
Compatibility is directional. Using MIT code in a GPL-3.0 project is generally fine, but using GPL-3.0 code in an MIT project means the distributed result must be licensed under GPL-3.0. License A is always the code you want to use; License B is the project it goes into.
Commercial use is not the same as proprietary use. Almost every open-source licence allows commercial use; the question that usually matters is whether you can keep your own source code closed when you distribute or host the result.
The engine is open source: @esdecode/license-checker on GitHub, including every rule and its tests.
What the results mean
- Generally Compatible
- The licence terms generally allow this use; notice obligations may still apply.
- Compatible With Conditions
- The use is generally possible if specific conditions are met, such as providing source code or allowing relinking.
- Potential Conflict
- A conflict is plausible depending on how the code is combined, distributed or licensed.
- Likely Incompatible
- The licence terms, as generally understood, do not permit this combination.
- Manual Review Required
- The terms are proprietary, custom or product-specific and must be read individually.
- Unknown
- A licence could not be identified, so no conclusion is drawn.