May 18, 2016 3:21 PM EDT

Robin Wright’s speech Tuesday at a Rockefeller Foundation event, in which she revealed that she demanded to be paid as much as Kevin Spacey, is just the latest example of stars speaking out on pay equality.

As two federal government agencies conduct an investigation looking into discrimination against female directors in Hollywood, Motto takes a look back at some of the key times stars have chosen to speak out about pay equality in the industry and in the world at large.

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Write to Robin Hilmantel at robin.hilmantel@time.com.

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