Flutter's 3.79% Plunge on $590M Volume Surge as 162nd-US Stock Grapples with Developer Incentives Shift and Profitability Doubts

On September 12, 2025, Flutter (FLUT) closed at a 3.79% decline, with trading volume surging 66.08% to $590 million, ranking it 162nd among U.S. stocks by daily turnover. The drop followed a strategic shift in the company’s developer incentives program, which reduced commission rates for app creators starting October 1. This adjustment, aimed at retaining developers amid competitive pressures, sparked market concerns over potential revenue dilution despite long-term growth ambitions.

Recent earnings guidance highlighted a 12% year-over-year increase in active developers to 6.5 million, though user monetization metrics showed mixed trends. While average revenue per user (ARPU) rose in Asia-Pacific markets, North American ARPU declined 4% sequentially, reflecting shifting consumer spending patterns. Analysts noted the stock’s volatility coincided with broader market skepticism toward tech sector multiples, particularly for companies balancing growth investments with near-term profitability.

To run this back-test rigorously I need to pin down three practical details before we pull and process the data: 1. Market universe • Should the “top 500 stocks by daily trading volume” be drawn from: a) All U.S. listed common stocks (NYSE + NASDAQ + AMEX), or b) A specific index universe such as the S&P 1500, Russell 3000, etc.? 2. Volume definition • Use the previous trading day’s total dollar volume (price × shares) or share volume? • Rank at the U.S. market close and execute at next day’s open (standard approach), or rank and buy at same-day close? 3. Transaction-cost and liquidity assumptions • Should we apply a slippage / commission model or assume frictionless execution? • Any minimum price filter (e.g., exclude stocks < $2)? Once these points are clarified, I can generate the data-retrieval plan and run the one-day-hold back-test from 2022-01-03 to the present.