Wizards of the Coast

Wizards of the Coast is the publisher of the Dungeons & Dragons roleplaying game (as well as D&D spinoff games like d20 Modern), and is the creator of the d20 System and the Open Game License. Wizards acquired the D&D game when they purchased TSR, Inc. in 1997, and were in turn acquired by Hasbro in 1999.

Wizards produced Open Game Content for the 3rd edition of Dungeons & Dragons, as well as for the 3e spinoff d20 Modern. This primarily took the form of a System Reference Document for each game, but also included a handful of Dragon Magazine articles and some limited OGC in select rulebooks. D&D 5th edition also saw the release of an SRD several years after the game was launched, which was much more limited than the 3.x SRD. However, it was accompanied by the debut of the Dungeon Masters Guild program, which allows third parties to publish products that use the entirety of official D&D 5e content (including the Forgotten Realms setting), sell their products through the official D&D web store, and potentially receive marketing from Wizards, in exchange for giving a substantial cut of all sales directly to Wizards.