The Mag 7 Stopped Trading as a Bloc: What Mega-Cap Dispersion Means for Index Risk
For years the largest technology companies moved together, a bloc that rose and fell as one. This earnings season broke that pattern: on the same theme, the same night, they split hard, some rewarded and some punished on a single variable, visible AI returns. That de-correlation of the index's heaviest components is the real structural story, and for anyone trading the index those names dominate, it changes the risk in a specific way.