License comparison
GPL-3.0 vs LGPL-3.0: linking and source
For an application you distribute, the library license changes the release work. GPL-3.0 requires a covered combined work to remain under the GPL with corresponding source. LGPL-3.0 permits your application to use other terms if you meet its Combined Work conditions, including applicable library-source duties and a way to use a modified library. Linking an LGPL library does not remove those conditions.
Compare the permissions, limits and obligations recorded in each guide. Read the license text for the full conditions that apply to your release.
Permissions
GPL-3.0-only
Commercial use
You may ship the code inside a paid product. The license does not restrict commercial use.
Modify
You may change the code, including keeping those changes private, unless a later obligation says otherwise.
Distribute
You may give copies to others. Distribution is what usually turns notice and source duties into real work.
Private use
Use inside your company, including internal forks, does not by itself trigger distribution duties.
LGPL-3.0-only
Commercial use
You may ship the code inside a paid product. The license does not restrict commercial use.
Modify
You may change the code, including keeping those changes private, unless a later obligation says otherwise.
Distribute
You may give copies to others. Distribution is what usually turns notice and source duties into real work.
Private use
Use inside your company, including internal forks, does not by itself trigger distribution duties.
Patent use
These licenses typically include a patent grant covering the licensed files. Read the grant before relying on it in a high-stakes deal.
Limits
GPL-3.0-only
Hold liable
The authors disclaim warranty. Recipients cannot hold them liable for damages arising from the software, except where law forbids that disclaimer.
Use trademark
The license is not a trademark license. Names, logos and product marks stay with their owners unless a separate grant says otherwise.
Open your product
Copyleft can reach a combined work you distribute, not only the original files. How far that reaches in your stack is a counsel question.
Network copyleft
Classic GPL has no network clause. Offering the program as a hosted service, without distributing a copy, does not by itself trigger the source offer.
LGPL-3.0-only
Hold liable
The authors disclaim warranty. Recipients cannot hold them liable for damages arising from the software, except where law forbids that disclaimer.
Use trademark
The license is not a trademark license. Names, logos and product marks stay with their owners unless a separate grant says otherwise.
Open your product
File- or library-scoped copyleft does not, on its face, force you to open your entire application. Reciprocity stays on the covered files.
Obligations
GPL-3.0-only
Include copyright
Keep copyright notices on distributed copies.
Include license
Give recipients a copy of the license with the program.
Disclose source
When you distribute a binary of a covered work, corresponding source has to be offered in the way the license describes.
Same license
The combined work you distribute has to stay under this license. You cannot close the covered work with a more restrictive grant.
Installation Information
Section 6 also asks for Installation Information when a binary ships in a User Product, so the owner can run a modified build on the device.
LGPL-3.0-only
Include copyright
Keep copyright notices on the covered files you distribute.
Include license
Keep the license text with the covered files, and say that those files are under this license.
Disclose source
Source for the library, including your modifications to it, has to be available to people who received a binary.
Keep replaceable
Recipients must be able to swap in their own build of the library. Dynamic linking is the usual path. Static linking means you also hand over a way to relink.
Installation Information
LGPL-3.0 rides on GPLv3, so a Combined Work in a User Product also owes Installation Information for a changed library.
License texts
Practical guidance for procurement review, not legal advice. Confirm high-stakes use with counsel.