Billionaire David Tepper Sold Most of Appaloosa's Position in Microsoft and Initiated a New Stake in an Artificial Intelligence (AI) Memory Stock Up Over 4,100% in the Past Year

Billionaire investor David Tepper's Appaloosa Management sold most of its Microsoft stake in Q1 2026 amid concerns about AI valuations and competition to the company's software moat. Tepper initiated a major new position in SanDisk, an AI memory company up 4,100% over the past year, recognizing the critical role of NAND memory in the AI supply chain as demand for data storage scales with larger AI models.