Semiconductor stocks plunge on AI spending doubts, erasing $1.3 trillion（約210兆円） in value

Semiconductor stocks are experiencing a sharp reversal after months of gains tied to AI infrastructure buildout. The immediate trigger is a confluence of concerns: Wall Street is reassessing whether the $650 billion（約100兆円） in AI capital expenditures announced by hyperscalers can deliver sufficient returns, especially as enterprises actively seek to constrain their AI spending and pricing pressure hits major AI service providers such as OpenAI and Anthropic. This has exposed an uncomfortable gap between sky-high valuation expectations and the fundamentals companies can actually deliver—exemplified by Samsung's report of record operating profit that still disappointed Wall Street because it failed to exceed expectations and revenue growth fell short of views.

The broader backdrop includes two additional headwinds: a more hawkish Federal Reserve outlook that could raise interest rates to combat inflation, and evidence of competitive pressure from Meta's plan to rent out excess AI computing capacity. These factors together have sparked a reassessment of the chip sector's near-term growth runway. Notably, hedge funds have also profited from shorting semiconductor stocks for the past month, adding momentum to the decline.

However, the bull case remains intact for now. Second-quarter 2026 semiconductor earnings are expected to grow 131%, and supply of high-bandwidth memory—the key driver of recent gains—is sold out through most of 2027, according to CNBC. The question now is whether earnings beats from industry giants like TSMC and Intel in mid-to-late July can restore confidence or confirm that valuations have run too far ahead of reality.