I’m not sure if she actually sued anyone but she had her lawyer(s) send out Cease & Desist letters in the 90′s, which threatened legal action (suing) on the fanfic writers if they did not Cease & Desist in the writing of fanfic, regardless of whether they were selling it or sharing it for free.

Too much to explain here, try my #war on fanfic tag and do the google for more info.