The FreeCAD application is licensed under the terms of the LGPL2+ license, as stated below.
The different libraries used in FreeCAD and their respective licenses are described on the Third Party Libraries wiki page.
Version 2, June 1991
Copyright (C) 1991 Free Software Foundation, Inc. 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. [This is the first released version of the library GPL. It is numbered 2 because it goes with version 2 of the ordinary GPL.]
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