Re: Compatibility of LGPL-3+ and LGPL-2.1 in same library.

According to the GNU compatibility matrix

https://www.gnu.org/licenses/gpl-faq.html#AllCompatibility[1]

the answer is that, without permission from the original copyright owners, you can 
combine the code if you re-license the combination as either GPLv3 or GPLv3+.  If you want 
the combined code to be LGPLv3+, you would need the permission of the copyright holders 
of the LGPLv2.1 to re-license it.  (This is described in the top part of the chart in the link 
above.)

Note that this answer is specific to the situation of mixing code that is LGPLv3+ and 
LGPLv2.1 in the same library.  In the different scenario of having one library that is LGPLv2.1 
and another that is LGPLv3+ in the same project, you can mix them without any issues or 
the need to re-license any code.  (This is described in the bottom of the chart in the link 
above.)

On Thursday, June 6, 2024 6:53:32 AM MST Arun Kumar Pariyar wrote:
> Dear Legal Team,
> 
> Can LGPL-3+ and LGPL-2.1 licensed code be used together in the same library,
> or is re-licensing required?
> Your guidance on their compatibility would be
> greatly appreciated.
> 
> Regards,
> ~ Arun Kumar Pariyar
> 

-- 
Soren Stoutner
[email protected]

--------
[1] https://www.gnu.org/licenses/gpl-faq.html#AllCompatibility

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