First documented by Ball & Brown (1968) and Bernard & Thomas (1989). Exploits the multi-week institutional accumulation window post-earnings driven by TWAP/VWAP block execution frictions.

Screened daily across S&P 500 constituents: Standardized Unexpected Earnings (SUE >= +2.0), positive revenue growth surprise, Sloan accrual quality ratio <= 0.10, and 20-day pre-earnings run-up < 25%.

TypeSafe Jev evaluates candidate surprise metrics, margin deltas, and qualitative guidance on the OpenRouter Decisions API, requiring P(QUALIFIED) >= 70% to eliminate guidance traps.

Target 10 to 15 equal-weighted positions held for 30 trading days (the core drift sweet spot). Managed with a 5% trailing ATR stop and mandatory exit before the subsequent quarter earnings print.