📚 Stock Market Glossary

Passive Frontrunning Drag is the systemic performance leakage experienced by index funds and ETFs resulting from predictable, rules-based benchmark rebalancing schedules.

Because inclusion methodologies (e.g., S&P 500, MSCI, KOSPI 200) are publicly documented, fast active hedge funds front-run prospective additions weeks in advance, bidding up stock prices before selling out at peak valuations to rules-bound passive indexers on the official effective date.

• Buy-High, Sell-Low Mechanical Trap: Passive funds are legally mandated to execute trades precisely at the closing price on the rebalancing effective date, systematically buying overbought additions and dumping oversold deletions.
• Hidden Compounding Fee: Imposes an invisible 20 to 50 basis points annual performance drag on ETF buy-and-hold investors beyond standard management expense ratios.
• Post-Inclusion Mean Reversion: Once the tsunami of passive buying clears on the rebalancing date, frontrunning hedge funds exit, causing freshly added stocks to suffer post-inclusion slumps.

Avoid buying stocks after formal index inclusion announcements, as active smart money is preparing to dump inventory on incoming ETF flows. Instead, utilize quantitative screening models to accumulate candidate names months prior, exiting on the final rebalancing date.