There were cases like this, but I also recall cases of many BBS's (which were all the rage before the internet) who shut down because they were carrying fan-produced D&D modules, and alternate RPGs based on D&D mechanics, but carrying different info (or even those without any D&D mechanics, but carried terms like "hit points" and "armor"). TSR legal discovered they were running, and the BBS admins were given two choices: either cease and desist carrying all D&D "derivative" material, or port all of that material over to TSR's approved BBS site with a notice on all of it that it belonged to TSR because it was derivative material. Most of them shut down rather than cease and desist, because it was either a measure of defiance, or because without that material their reasons to exist practically vanished. I saw one do this firsthand (can't recall the name now), and a lot of sites on the internet who years later had the cease and desists as well as the shutdown "defiance" notices of the BBS'es, as sort of a "gone but not forgotten" monument.