The Hollywood Reporter said anonymous sources confirmed that the executives had believed the messages criticizing management were private, but another employee found the messages and reported them.
The news outlet said one of the executives who was criticized was Netflix's Chief Marketing Officer Bozoma Saint John, and another was VP Netflix Original Films Marketing Jonathan Helfgot.
Co-CEO Ted Sarandos said the employees had been making comments critical of their peers, not about management.
He reportedly said the streaming giant does not "proactively monitor" employees on Slack, but the channel had been open so anyone could access the conversation, even though the employees had not realized that.
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