Nvidia Stock Plunges 15%—Biggest Loss In History—As DeepSeek Alarm Shakes AI Darling

1. Nvidia shares plunged 15%, marking its worst daily loss since March 2020. 2. The company lost about $520 billion in market cap, a historic one-day drop. 3. Nvidia's valuation fell to $2.98 trillion, losing its title of most valuable company. 4. DeepSeek's cheaper AI model challenges U.S. dominance in generative AI. 5. Nvidia CEO lost $17 billion in net worth due to the stock drop.