Vanity vs. Consequence: The Second Time in History the S&P Has Decoupled from the NASDAQ — Because of Authorship.

On Friday morning, October 2025, the market did something it almost never does.

The S&P 500 broke away from the NASDAQ — not by basis points, but by behavior.

It was the second time in recorded history that the two indices, normally locked in near-perfect correlation, diverged in their tempo and direction.

And it happened not because of policy, not because…