September split the industry in two. Fundamental equity long/short funds lost about 0.55%, while systematic equity long/short gained about 3.46%, its best month of 2026, according to performance data reported by Reuters. The lesson is more useful than the league table: when index direction is hostile and single-name dispersion is high, process design matters more than the generic label “equity hedge.” A discretionary book may have been hurt by crowded AI longs and short squeezes while a systematic book harvested the same cross-sectional movement. Reuters report · HFR market commentary
That divergence belongs beside the IMF’s new system-level warning. Hedge-fund gross assets have tripled since 2013 to about $13 trillion, with roughly $40 trillion of gross notional exposure. The IMF’s actual mechanism is the point: leverage, crowded positions and correlated redemptions can turn liquidity suppliers into forced sellers. Its sample finds the most crowded stocks about 10 percentage points more volatile than the least crowded, with drawdowns roughly 4 points deeper. Prime-broker discipline, financing tenor and redemption concentration therefore belong in portfolio-risk conversations, not in a separate “financial stability” drawer. IMF analysis