MSFT, NVDA, AAPL and META alone added about 300 points to the S&P in Q3, more than 200% of the index's total gain. The other 499-ish stocks together subtracted about 150 points: Citadel

01 THE MACHINE READ

WHY IT MATTERS.

Extreme mega-cap concentration means index gains depend on a handful of names, amplifying drawdown risk if they falter.

02 THE STORY SO FAR

THE RECORD, IN ORDER.

STANDALONE ITEM — NOT YET FOLDED INTO A DEVELOPING STORY.

03 WHO'S INVOLVED

ENTITIES ON FILE.

04 RECEIPTS

THE SOURCE RECORD.

05 PROPAGATION

WHAT THIS TOUCHES.