Now his co-star Law, who plays Albus Dumbledore in the series, has spoken about the decision.
Talking to Entertainment Tonight, Law said: "In a situation like this, you defer to the studio. That's all you can do. Because you have to turn up and play your part.
"It was unusual for me because, in fact, on this particular role. Johnny had actually only done a day's filming, I think, on his own.
"In a franchise like this, it's the studio and the company that make the big decisions. And you have to go along with those, because we're just a member of the team."
Depp filed a libel case against the Sun after an article labeled him a “wife beater,” referring to his marriage to actress Amber Heard.
However, judges found in favor of the British tabloid, and though Depp plans to appeal the decision, he took to social media a few days after the ruling to tell how Warner Bros. bosses requested he resign.
The post on Instagram read: "In the light of recent events, I would like to make the following statement.
"Firstly, I'd like to thank everybody who has gifted me with their support and loyalty.
"I have been humbled and moved by many of your messages of love and concern, particularly over the last few days.
"Secondly, I wish to let you know that I have been asked to resign by Warner Bros. from my role as Grindelwald in Fantastic Beasts and I have respected and agreed to that request.
"Finally, I wish to say this.
"The surreal judgement of the court in the U.K. will not change my fight to tell the truth and I confirm that I plan to appeal.
"My resolve remains strong and I intend to prove that the allegations against me are false. My life and career will not be defined by this moment in time.
"Thank you for reading.”
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