The AI trade, which carried markets through much of the past two years, is having a rough week. The S&P 500 and Nasdaq are both on track for weekly losses, with the damage concentrated almost entirely in one sector: semiconductors.
The semiconductor selloff, by the numbers
Nvidia closed down 4.2% at roughly $200 on June 25, landing it the dubious honor of worst performer in the PHLX Semiconductor Index year-to-date.
Earlier in June, Nvidia shed over $300 billion in market capitalization during a concentrated AI-chip selloff, a loss roughly equivalent to wiping out entire large-cap companies in a matter of days.
AMD did not escape the carnage either. Shares fell as much as 5.8% in a single session and dropped sharply from a mid-June high of $542.52 down to around $452.40.
Micron took some of the heaviest hits in the group, with shares declining between 9% and 11% over the same period. Broadcom and Intel also underperformed, confirming this was not a company-specific story but a sector-wide repricing.
Why the chip sector matters so much to the broader market
The PHLX Semiconductor Index’s weakness over the week of June 23-26 acted as a drag on both the S&P 500 and Nasdaq. This is the mechanical reality of how index construction works: a handful of large-cap names moving sharply downward pulls the whole index with them, regardless of how the remaining hundreds of stocks perform.
What this means for investors watching the AI trade
The AMD move is particularly worth watching. A drop from $542.52 to around $452.40 over a matter of weeks is a significant technical shift, moving the stock well off highs that had been established during peak AI optimism in mid-June. Traders who entered positions at or near those highs are now sitting on substantial drawdowns, which creates selling pressure as stop-losses trigger and risk managers reduce exposure.
Micron’s 9% to 11% decline deserves separate attention. Memory chips are often treated as an economic bellwether because demand for memory is tied closely to actual build-out activity in data centers and consumer electronics. When memory stocks sell off this sharply, it can indicate that real-world demand is not keeping pace with the projections that were baked into elevated valuations.