In December 2020, AI ethicist Timnit Gebru left Google.[40] While the exact nature of her quitting or being fired is disputed, the cause of the departure was her refusal to retract a paper entitled “On the Dangers of Stochastic Parrots: Can Language Models be Too Big?”[40] This paper explored potential risks of the growth of AI such as Google Brain, including environmental impact, biases in training data, and the ability to deceive the public.[40][41] The request to retract the paper was made by Megan Kacholia, vice president of Google Brain.[42] As of April 2021, nearly 7000 current or former Google employees and industry supporters have signed an open letter accusing Google of “research censorship” and condemning Gebru's treatment at the company.[43]