http://blog.wired.com/underwire/2008/05/no-poison-pill.html
No 'Poison Pill' in New D&D License
By Lore Sjoberg EmailMay 02, 2008 | 8:06:00 PMCategories: Games
Dungeon_masters_guide
Contrary to rumors, the upcoming fourth edition of Dungeons and Dragons will not require third-party publishers to choose between developing material for the new edition and continuing to support the current edition of the game.
D&D publisher Wizards of the Coast made a public-relations saving throw Friday, telling Wired.com that "publishers will decide -- on a product line by product line basis -- which platform to use when developing their products." This contradicts earlier, unconfirmed message board posts that suggested each company would have to decide which edition to exclusively support.
This supposed "poison pill" clause angered many gamers and publishers, and cast doubt on the ability of publishers like Paizo, creators of the upcoming backward-compatible Pathfinder Roleplaying Game, to cater to fans of both editions.
Paizo's game will be licensed under the same Open Gaming License as D&D 3.5, meaning other game companies will be encouraged to write and sell material for it. The game is in