Proprietary software that uses Tk (software)

PyMOL is a source-available molecular visualization system created by Warren Lyford DeLano. It was commercialized initially by DeLano Scientific LLC, which was a private software company dedicated to creating useful tools that become universally accessible to scientific and educational communities. It is currently commercialized by Schrödinger, Inc. As the original software license was a permissive licence, they were able to remove it; new versions are no longer released under the Python license, but under a custom license (granting broad use, redistribution, and modification rights, but assig