This is a complicated story that's been made murkier by politics, I'm honestly not sure where the best starting place is. Marcy Wheeler is has been researching and documenting a whole cloud of related stories. These two are probably no worse than others as starting points.
https://www.emptywheel.net/2017/01/04/why-was-gru-using-open...
https://www.emptywheel.net/2017/03/28/what-was-the-relations...