Plunging 10% in a Single Week, Falling Sharply for Three Consecutive Weeks, and Retreating 20% from Highs! The "AI Bull …

The Philadelphia Semiconductor Index plummeted nearly 10% in a single week, with a cumulative retreat of over 20% from its June highs, officially entering a technical bear market. Goldman Sachs characterized this as "one of the largest momentum strategy sell-offs on record." The primary cause was not a deterioration in fundamentals, but rather the concentrated unwinding by hedge funds of the year's hottest pair trade—"long semiconductors, short cloud computing providers"—compounded by concerns over overinvestment triggered by Taiwan Semiconductor's capital expenditure warning. The wave of selling has swept across global tech stocks