licensecompat checker

Mozilla Public License 2.0 (MPL-2.0)

File-level copyleft. Modified MPL files must stay MPL and be disclosed; your own new files can be any license. GPL-compatible via secondary-license mechanism (unless a file is marked 'Incompatible With Secondary Licenses').

Key facts

SPDX id
MPL-2.0
Category
Weak copyleft
Copyleft scope
file
Express patent grant
Yes
SaaS triggers disclosure
No
GPL-compatible
Yes — compatible with the GPL.

Obligations

When redistributing as open source.

Internal use only (never distributed)

  • MPL-2.0: retain the copyright notice and license text.
  • MPL-2.0: state significant changes made to the code.

Public SaaS / hosted web service

  • MPL-2.0: retain the copyright notice and license text.
  • MPL-2.0: state significant changes made to the code.

Commercial use

Yes. Copyleft is scoped to modified MPL-2.0 files — your own new files can stay proprietary. Disclose modified MPL-2.0 files when you distribute.

Permissive: include notices (Apache also needs NOTICE + change statements). Weak copyleft: disclose only the modified library/files and, for LGPL static linking, provide a relink path. Strong copyleft (GPL): NOT possible to keep proprietary if GPL code is in the derivative work. AGPL: same as GPL plus network rules.

FAQ

Can I use MPL-2.0 in a commercial product?
Yes. Copyleft is scoped to modified MPL-2.0 files — your own new files can stay proprietary. Disclose modified MPL-2.0 files when you distribute.
Do I have to open-source my code if I use MPL-2.0?
Only modified MPL-2.0 files, and only when you distribute. Your own new files are not affected.
Does running MPL-2.0 software as a SaaS require source disclosure?
No. Hosting is not distribution under MPL-2.0; running it as a service does not trigger source disclosure.
Is MPL-2.0 compatible with the GPL?
Yes — compatible with the GPL.

Compatibility with other licenses

Open the checker with MPL-2.0 selected