From our Frequently Asked Questions:
Q: How is Chaosium and its games affected by the Dungeons & Dragons' Open Gaming Licence controversy?
A: Call of Cthulhu, RuneQuest, Pendragon, 7th Sea, Rivers of London, Questworlds and the rest of the Chaosium family of games are utterly unaffected by whatever happens with Wizards of the Coast's D&D OGL.
Q: What about the D20 version of Call of Cthulhu?
A: The D20 version of Call of Cthulhu is now l-o-n-g out-of-print and the license expired. In any case, the credits page included the statement, "This WIZARDS OF THE COAST® game product contains no Open Game Content."
Q: Does Chaosium have its own Open Game License?
A: We issued our own (non-WotC) Open Game License for the Basic Roleplaying System in 2020, enabling designers to create their own roleplaying games using the Basic Roleplaying rules engine, royalty-free and without further permission from Chaosium. At the time, we raised concerns about serious deficiencies and legal uncertainties in the WoTC OGL, especially if it was being used for non-D20 games.
Q: What about Paizo's OGL initiative?
A: Chaosium is part of the Open RPG Creative License initiative aka 'ORC', announced by our friends at Paizo. It is intended that this system-neutral open RPG license can be freely used across the tabletop RPG industry. Chaosium is part of the initial cohort of companies involved, along with Green Ronin, Kobold Press, Legendary Games, and Rogue Genius Games. Since then, many more tabletop RPG companies have signed on to the initiative.
In all likelihood we will switch our own Open Gaming License model to the ORC in due course.