Canthology is released under a set of free/open-source licenses:
- The Canthology software is released under the GPL 3.0 copyright license.
- The Canthology User Guide manual is released under the GNU FDL 1.3 copyright license.
- Most of the bundled ".sty" files are released under the LaTeX Project Public License. The only exception is "hevea.sty", which is the copyright of Luc Maranget. As far as I am aware, he considers that file to be in the public domain.
- The ".hva" files are released without any explicit copyright license attached to them. Please consider these to be in the public domain.
The above copyright licenses apply only to the Canthology software and its documentation; they do not apply to whatever documents you write with the aid of Canthology.