has clause licence software license No restrictions on derivatives derivative code same license Source code available Usage unrestricted Distribution unrestricted License without restrictions on derivatives GNU Project Free License Type Distribution with notices GNU LGPL http://en.wikipedia.org/wiki/GNU_Lesser_General_Public_License, accessed 27 March 2015. Allyson Lister GNU Lesser General Public License The GNU Lesser General Public License (LGPL) is a free software license published by the Free Software Foundation (FSF). The license allows developers and companies to use and integrate LGPL software into their own (even proprietary) software without being required by the terms of a strong copyleft license to release the source code of their own software-parts. The license requires that only the LGPL software-parts be modifiable by end-users via source code availability.