How can we answer questions about tabletop game rules without infringing copyright?

Question

https://rpg.stackexchange.com/ is a stack dealing with table top RPG games, the most prominent being Dungeons and Dragons (D&D). Answering questions almost always relies on information from rule books sold by the makers of D&D.

Due to stack culture reasons, answers directly referencing the rules are valued far more than experienced perspectives. To avoid link rot, it is essentially a requirement to copy-paste the relevant portions of the rules into the answer. These portions could be a few sentences, or even a few paragraphs, often they are the entire rules for a spell or character ability.

Even answers that do not directly quote the rule books often use information from those rulebooks to write an answer.

Ultimately SE is using this content to turn a profit, so we can't naively think we are merely sharing information with friends and are immune to copyright law. Are we actually allowed to share this pay-walled information? To what extent is this kind of content infringing copyright? What should we be looking out for to prevent issues?

Answer 1

This kind of quotation, for commentary, criticism, or reference, is generally allowed without obtaining permission. In the US, this falls under fair use (see 17 USC 107. In the UK and most commonwealth countries, it falls under fair dealing. In other countries there are various exceptions to copyright that will probably cover this.

Even answers that do not directly quote the rule books often use information from those rulebooks to write an answer.

Facts and ideas are never protected by copyright, so this is not going to be an issue. See 17 USC 102(b), which provides:

(b) In no case does copyright protection for an original work of authorship extend to any idea, procedure, process, system, method of operation, concept, principle, or discovery, regardless of the form in which it is described, explained, illustrated, or embodied in such work.

As a comment by user Trish reminds, game rules are facts and are not protected, although their exact wording may be.