I'm not sure about links directly to court cases, but here's a couple different general-consumption articles from the last few years that address this sort of thing. I'm hopeful I didn't convey that the consensus on the subject is particularly solid...
Thanks for the links. I know little on the topic. It may be a while before a litigious content owner identifies their work as having contributed to another generated one. I have yet to see in-your-face examples being monetized.
From a technical standpoint using copyrighted text to train a text translator is similar to using copyrighted movies to train a movie generator. Which of these are acceptable?
The nearest neighbor precedent I'm aware of is the dismissal of Authors Guild v Google