Post-Earnings Drift: A Real, Documented Edge That Is Not Yours on a Short Timeframe
Post-earnings announcement drift is one of the most durable anomalies in finance: stocks that surprise on earnings keep drifting in that direction for months. It is real, documented since 1968, and genuinely a tradeable edge, for investors on a 60-to-90-day horizon. For a short-dated options trader, it is nearly invisible, and understanding why is a lesson in how your timeframe determines which edges are even available to you.