S&P Revises Growth-Value Stock Rules, Affecting $375B in Index Funds

The quiet significance here is methodological: S&P is effectively conceding that book-value and momentum screens misclassify modern, intangible-heavy companies, which means the growth/value label is becoming a product of accounting choices rather than a stable economic trait. The forced rebalancing concentrates real trading into a single pre-open window, so the affected $375 billion faces implementation and liquidity risk that has nothing to do with fundamentals. Whether the revised criteria produce more durable style separation, or just a one-off reshuffle that funds must absorb, is the open question worth tracking after Dec. 21.