If a man interrupts you whilst you are speaking at work/uni/conf, do not pause, do not hesitate, do not give way. Keep talking, slightly louder, as if he never said anything, until it becomes clear to everyone that he’s interrupting your flow of speech which was already ongoing.

If he repurposes something you just said, and claims it as his own knowledge - call it out clearly. If you watch this happen to a woman and she can’t call it out - you do it as the observer.

All it takes is

“She just said that exact same thing. That was her idea.”

If you observe a woman being interrupted repeatedly, say something.

Say

“Could you let her finish please? I want to hear what she has to say.”

That’s all it takes.