---
title: US stock market concentration is at unprecedented levels
description: "US tech stocks now account for nearly 50% of US stock market capitalization, an all-time high.\n\nThis is ~9 percentage points above the 2000 Dot-Com Bubble peak.\n\nThe top 10 stocks alone represent a record 40% of the S&P 500's market cap, ~13 percentage points above the Dot-Com Bubble peak.\n\nSource: Global Markets Investor"
---

[Syz The Moment](https://blog.syzgroup.com/syz-the-moment)

# [US stock market concentration is at unprecedented levels](https://blog.syzgroup.com/syz-the-moment/us-stock-market-concentration-is-at-unprecedented-levels)

 Written by [Charles-Henry Monchau, CFA, CMT, CAIA](https://blog.syzgroup.com/syz-the-moment/author/charles-henry-monchau) | Aug 11, 2026, 3:36:42 PM

[View full post](https://blog.syzgroup.com/syz-the-moment/us-stock-market-concentration-is-at-unprecedented-levels)

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