Hank Pym’s distaste for Howard Stark is evident from the first time they’re shown on screen together in Ant-Man, however one theory suggests that a scene in Avengers: Endgame might explain why Pym hates Stark quite so much. Through the whole MCU Hank Pym is shown to be cantankerous and abrasive. While he has little patience for most people, Scott Lang included, his contempt for Howard Stark goes further than for anybody else.
In the opening flashback scene from 1989 at the start of Ant-Man, Hank
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