GPL is a free software license. For a license to be a free software license, it must guarantee the 4 essential freedoms: https://www.gnu.org/philosophy/free-sw.

GPL is a free software license. For a license to be a free software license, it must guarantee the 4 essential freedoms: https://www.gnu.org/philosophy/free-sw.en.html#four-freedoms https://www.gnu.org/philosophy/free-sw.en.html#four-freedoms