The (https://www.cnbc.com/2026/08/21/jpmorgan-worries-about-autumn-downturn-in-stocks.html) gets the headline right but the mechanism wrong. It's not P/E compression that breaks this rally—it's the forensic signal nobody's watching: C-suite liquidation at all-time valuations. Cerebras CEO just offloaded 7,277 shares at $214–$217 on Aug 18. CrowdStrike's Kurtz dumped 6,120 shares at $198–$201. Cloudflare's CLO moved 2,538 shares at $304.68.

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