SketchChair is open-source software and is released under the GNU General Public License v3.0.
GitHub SketchChair Code Repository
SketchChair is built with help from Processing, and uses libraries under the following licenses:
Processing Export Libraries
GNU Lesser General Public License (LGPL)
OpenGL, JOGL, GLUEGEN - Open Graphics Library
SGI Free Software License B v2.0, BSD and Apache Licenses.