"Don't be evil." was dropped in 2015 or thereabouts IIRC. I'd guess when they realised it was becoming more of a joke than a motto: "Google, the company who's motto is 'don't be evil' angered customers again today when ...
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The new code of conduct has a close approximation of the philosophy—though perhaps more formally phrased—in the very first sentence of the preface: "Employees of Alphabet... should do the right thing – follow the law, act honorably, and treat each other with respect."
