When you hear a rumor, to not spread it you have to keep it to yourself. If you regurgitate it in any context, whether maliciously or to merely start a discussion, and the person with whom you are having the discussion, or anyone around, has never heard about it, well then you've just spread the rumor. That is the definition of spreading rumors. This many people knew the rumor... you opened your mouth around virgin ears... and now more people know the rumor. A fairly simple concept, really...