Cross accepted Carson’s purchase offer for the technology, and Carson showed up later inAnt-Man with some of his HYDRA buddies to make the transaction.
Oh, and because Hank slammed his head into a table when he made an insulting comment about Janet van Dyne’s death.
Thanks to Scott Lang, Hope van Dyne and the Antourage, the sale didn’t go through as planned, and while Cross later died fighting the new Ant-Man, Carson managed to steal the briefcase containing Cross’ version of the Pym Particles (getting bitten by some ants in the process) and escape the Pym Technologies building before it exploded.
For those of you who need a refresher, Mitchell Carson is S.H.I.E.L.D.’s former Head of Defense who carried a grudge against Hank Pam dating all the way back to the late 1980s, frustrated that the scientist wouldn’t share how to create Pym Particles.