licensecompat checker

GNU GPL 3.0 only (GPL-3.0-only)

Strong copyleft with patent and anti-tivoization terms. Compatible with Apache-2.0, AGPLv3, LGPLv3. Incompatible with GPLv2-only. SaaS does NOT trigger disclosure.

Key facts

SPDX id
GPL-3.0-only
Category
Strong copyleft
Copyleft scope
strong
Express patent grant
Yes
SaaS triggers disclosure
No
GPL-compatible
GPLv3 family — compatible with GPLv3, AGPLv3, and LGPLv3.

Obligations

When redistributing as open source.

Internal use only (never distributed)

  • GPL-3.0-only: retain the copyright notice and license text.
  • GPL-3.0-only: state significant changes made to the code.

Public SaaS / hosted web service

  • GPL-3.0-only: retain the copyright notice and license text.
  • GPL-3.0-only: state significant changes made to the code.

Commercial use

Commercial use is permitted, but distributing the combined work requires releasing the whole work under GPL-3.0-only with source. A closed-source binary is not possible.

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 GPL-3.0-only in a commercial product?
Commercial use is permitted, but distributing the combined work requires releasing the whole work under GPL-3.0-only with source. A closed-source binary is not possible.
Do I have to open-source my code if I use GPL-3.0-only?
Yes, when you distribute — the combined work's source must be provided under GPL-3.0-only. Internal use and SaaS hosting do not trigger it.
Does running GPL-3.0-only software as a SaaS require source disclosure?
No. Hosting is not distribution under GPL-3.0-only; running it as a service does not trigger source disclosure.
Is GPL-3.0-only compatible with the GPL?
GPLv3 family — compatible with GPLv3, AGPLv3, and LGPLv3.

Compatibility with other licenses

Open the checker with GPL-3.0-only selected