Officially: Same answer as http://meta.rpg.stackexchange.com/questions/357/what-constitutes-copyright-infringement

The site deliberately has no opinion on this, it's up to posters to not plagarize. Also, the site is not a signatory to the OGL, the Community Use Policy, or any other publisher agreements outside of federal law.

Personal thought: Post brief excerpts of rules, which are likely covered by fair use, and link to fuller stuff where possible.

Officially: Same answer as What constitutes copyright infringement?

The site deliberately has no opinion on this, it's up to posters to not plagarize. Also, the site is not a signatory to the OGL, the Community Use Policy, or any other publisher agreements outside of federal law.

Personal thought: Post brief excerpts of rules, which are likely covered by fair use, and link to fuller stuff where possible.