Open gaming

Open gaming is a movement within the tabletop role-playing game (RPG) industry with similarities to the open source software movement. The key aspect is that copyright holders license their works under public copyright licenses that permit others to make copies or create derivative works of the game.

A number of role-playing game publishers have joined the open gaming movement, largely as a result of the release of the original System Reference Document (SRD) by Wizards of the Coast, which consisted of the core rules of Dungeons & Dragons 3rd edition. Open gaming has also been popular among small press role-playing game and supplement authors.

The use of the term open gaming began with the publication of the SRD and the simultaneous release of the Open Game License (OGL). However, role-playing games had been licensed under open and free content licenses before this.

The Fudge role-playing game system was created in 1992 by Steffan O'Sullivan with extensive help from the rec.games.design community. The name stood for "Freeform Universal Donated Game Engine" until Steffan O'Sullivan changed 'donated' to 'DIY' in 1995.

One reason why Fudge succeeded is that the author released it under the "FUDGE Legal Notice", a license that removed most restrictions on non-commercial use. However the FUDGE Legal Notice (more commonly known as simply "the Fudge license") was never intended to cover any work other than its eponymous role-playing game. Derivative works which were to be distributed for a fee required written permission from Fudge's author, Steffan O'Sullivan. The details of the Fudge Legal Notice were modified and expanded from time to time as O'Sullivan updated his work, but the essential elements of the license remained unchanged. The 1993 FUDGE Legal Notice allowed reprinting of the Fudge rules, including in otherwise commercial works, as long as certain conditions were met. The 1995 FUDGE Legal Notice permitted the creation of derivative works for personal use and for publication in periodicals.

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