Billionaire Stanley Druckenmiller May Have Just Repeated His "Big Mistake" With Nvidia -- This Time With a Chip Stock That Rose 300% in the First Half of 2026

The article argues that Stanley Druckenmiller may have exited Micron too early after Duquesne Family Office initiated a Micron position in Q1 2026 and fully closed it by Q2. The stock rose more than 300% in the first half of 2026, driven by booming demand for high-bandwidth memory and advanced DRAM tied to AI training and inference. Micron also crossed the $1 trillion market-cap milestone and secured multiyear supply agreements, strengthening the case that the AI memory cycle may be more durable than a traditional boom-bust pattern. Still, the piece notes valuation and supply-addition risks after such a sharp rally, suggesting Druckenmiller may have been locking in gains rather than making a clear mistake. The market takeaway is mixed: momentum remains strong, but the stock’s rapid run-up leaves it vulnerable to mean reversion.