Emil Michael, the U.S. Deputy Secretary of Defense for Research and Development, has sold his shares in the AI company Perplexity for between $5 million and $25 million, as disclosed in financial records. Michael, who serves as the Pentagon's chief technology officer, was previously involved with the startup's advisory board prior to his appointment during Donald Trump's administration. Earlier this year, he also sold his stake in xAI, which also fetched up to $25 million.