Last month, Blake Lemoine went public with his theory that Google's language technology is sensitive and therefore should have his wishes respected.
Google, in addition to several artificial intelligence experts, denied the claims and on Friday the company confirmed that he had been fired.
Lemoine told the BBC he is receiving legal advice and declined to comment further.
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In a statement, Google said Lemoine's claims about The Language Model for Dialogue Applications (Lamda) were totally unfounded and that the company worked with him for many months to clarify this.
It is therefore regrettable that despite a long commitment to this issue, Blake still chose to persistently violate clear employment and data security policies that include the need to safeguard product information, according to the statement.