Tech's Grip On S&P 500 Hits Record 39% As AI Rally Pushes Concentration Beyond Dot-Com Peak - Marvell Tec

Tech stocks surpass 50% of S&P 500 index for first time

Tech sector reaches 39.4% of S&P 500; Mag7 (Nvidia, Microsoft, Apple, Amazon, Alphabet, Meta, Tesla) represent a third of the index. Synchronized downturn cascades to passive index funds and 401k portfolios; Nvidia remains critical AI infrastructure provider.