Hari Krishnan

GM101: When Passive Breaks the Market ft. Hari Krishnan & Cem Karsan

- Harry Markowitz and colleagues published "A Model for Passive That Breaks the Market," arguing that rising passive investment share (now ~50–55% of US equities) decouples stock prices from fundamental value and increases market instability without requiring net outflows. - The paper models how above ~83% passive share, volatility can increase uncontrollably at a cubic rate; at ~91%, markets could theoretically approach zero in finite time under extreme conditions—not a prediction, but a structural risk analysis. - Markets have transformed from **value-driven to flow-driven**, where reflexive dynamics dominate fundamentals. Passive flows now determine price direction more than earnings or economic data, making volatility feed back on itself. - Concentration and leverage in mega-cap equities accelerate under passive flows: names receiving large dollar allocations push prices up faster than smaller, more elastic names, creating feedback loops that boost earnings and attract more capital. - Government entities (Fed, Treasury) are acutely aware that $500 trillion in global long assets dwarfs their direct tools; proactive market management through communication and positioning has become necessary to prevent systemic breaks. - Upside risks from continued reflexive buying compete with downside risks from sudden deleveraging or rate shocks that could trigger a 2022-style reversal across correlating assets and strategies.