Woofun AI data shows that the semiconductor sector's weight in the S&P 500 index has climbed to a record 19.7%, representing a near fourfold increase from 2020 levels driven by artificial intelligence investment.

This expansion has concentrated index performance around tech and chip leaders, raising concerns about excessive concentration and high valuations.

However, sustained ETF inflows continue to support the sector, while investors monitor whether AI capital expenditures can justify current pricing.