Opendoor's 14.43% Surge on $2.5B Volume Ranks 32nd as Strategic Shifts Boost Liquidity

On October 6, 2025, Opendoor (OPEN) surged 14.43% with a trading volume of $2.5 billion, ranking 32nd among U.S. stocks by volume. The move followed a strategic shift in its iBuying model, which reduced price concessions on home purchases by 15% and expanded into four new Sun Belt markets. The company also announced a $300 million asset-backed loan facility to accelerate inventory turnover. Analysts noted the adjustments could improve liquidity metrics and reduce exposure to interest rate volatility in its real estate portfolio.

Market participants highlighted the timing of the announcement ahead of the Federal Reserve's policy decision week. The loan facility's structure—secured against 65% of home valuations—was seen as a risk-mitigation measure compared to unsecured debt used in previous quarters. Short interest data showed a 22% decline in open short positions over the past month, suggesting reduced bearish sentiment ahead of the earnings report scheduled for October 23.

To run this back-test accurately I need a few details that aren’t yet specified: 1. Universe • Do you want all U.S. listed common stocks (≈ 4,000 names) or a narrower group such as the S&P 500 constituents? 2. Trading convention • Enter at that day’s close and exit at the next day’s close (T + 1), or use next-day open/close prices? • Equal-weight all 500 names each day, or weight by their trading volume / market-cap? 3. Transaction costs & slippage • Should we assume zero costs, or apply a standard commission and bid-ask slippage? 4. Survivorship bias • Is it acceptable to use today’s active-tickers list, or should we reconstruct the historical universe (includes delisted firms)? Once these points are settled I can fetch the data, generate daily portfolios, and run the back-test from 2022-01-03 to today.