The last film in the series, Star Trek Beyond, despite critical acclaim, didn’t perform up to expectations financially, and supposedly Paramount and Skydance Media wanted the two stars to take less money than their existing deals called for, leading to the impasse.
After S.J. Clarkson was hired last April to be the franchise’s first female director, news came in August that the fourth film may not include Chris Pine and Chris Hemsworth due to contract talks falling through.