PWI had an in-depth article regarding how the situation between AJ Styles and TNA deteriorated to the point that TNA felt it was perfectly fine to make it public and trash Styles a bit.
According to PWI, talks started in November with TNA wanting Styles to be signed by the time they'd debut on POP in January. Anderson and Gallows got involved from a suggestion by one of the sides in the talks.
All three supposedly had a personal meeting with Dixie in December over potential contract details and debut storylines. TNA claims all three signed a deal while all three denied it actually happening. The big key is no lawyers for either side were involved so its very likely this deal was just a non-legally binding "gentleman's agreement" instead.
Once Styles' lawyer got involved, whatever deal was made was likely voided since TNA knew his lawyer would be against any deal made without his involvement beforehand. Anderson and/or his lawyer likely rejected the deal due to the lower than expected offer given.
Around the same time, the WWE got involved and basically outbid TNA which is why all three (plus Nakamura) are going to the WWE. TNA got furious once Styles' lawyer said the talks were off and hinted a deal with WWE was already done.
Being rumored TNA might consider legal action against Styles and the WWE but would need to prove the documents signed by all three guys were legit contracts.
http://www.pwinsider.com/article/992...-here.html?p=1