In 1999 I helped Wizards of the Coast develop and deploy the Open Gaming License (aka the OGL). In 2000, we released the rules of Dungeons & Dragons via that license using a mechanism called a System Reference Document to clearly and unambiguously indicate what content was now Open Game Content.
In parallel I created a website for an organization I called the Open Gaming Foundation which has no legal existence but represents my hopes and aspirations for the long term success of the movement for Open Gaming, which promotes the idea that the rules for games should not by restricted by copyright and should be free to be used, modified, and redistributed in any legal manner, much like the principles of the Open Source Software movement.
The Open Gaming Foundation website continues to exist and provide references to those who seek them.
