Castle Securities CEO Griffin said investors are almost certainly in an AI bubble, likening current market dynamics to those before the dot-com bust and pointing to some fanciful business models. He added he regretted selling his Amazon shares before that crash. Griffin, who earlier called AI “garbage” at Davos, told a Stanford Business School audience in May that the technology’s potential leaves him “depressed.”

2026-10-21

Castle Securities CEO Griffin said investors are almost certainly in an AI bubble, likening current market dynamics to those before the dot-com bust and pointing to some fanciful business models. He added he regretted selling his Amazon shares before that crash. Griffin, who earlier called AI “garbage” at Davos, told a Stanford Business School audience in May that the technology’s potential leaves him “depressed.”