JACK-5 finished collecting fight data at The King of Iron Fist Tournament 5 and headed back to the G Corporation's laboratories. Jane used this data in her research to develop more sophisticated combat algorithms for him.
While G Corporation was at war with the Mishima Zaibatsu, mass-produced JACK units were deployed around the world. Unconfirmed reports claimed the Mishima Zaibatsu had begun manufacturing a copy of the JACK unit designed for large-scale massacre. Jane was angry that JACK was being imitated, so she sent in the more sophisticated model JACK-6 in order to investigate the truth behind the rumors.