Bio Plunges 50.4% to 489th in Market Activity Amid Biotech Sector Turbulence

Bio closed at $0.22 billion in trading volume on October 3, 2025, marking a 50.4% decline from the previous day’s volume and ranking 489th in market activity. Bio-Techne (TECH) rose 1.39% amid sector-specific developments.

Recent regulatory updates in biotech licensing frameworks created a mixed impact, with some firms facing delayed approvals while others benefited from streamlined processes. Analysts noted that Bio’s performance correlated with sector-wide volatility, as investors recalibrated expectations for R&D timelines and capital allocation strategies. Market participants emphasized the importance of near-term clinical trial disclosures in shaping momentum.

To construct an accurate back-test I’ll need to pin down a few practical details about the strategy and the data universe. Could you please confirm (or amend) the following? 1. Market universe • U.S. listed equities (NYSE + NASDAQ), or a different universe? 2. Re-balancing mechanics • Each trading day we rank all stocks by that day’s dollar trading volume, buy an equal-weighted basket of the top-500 at that day’s close, and liquidate the basket at the next day’s close. • Is the equal-weight assumption acceptable? • Should we include simple transaction costs (e.g., 5 bp per side), or ignore them? 3. Pricing convention • Buy and sell at the daily close price, or would you prefer open-price execution? Once those points are settled I can generate the daily signals and run the back-test from 2022-01-03 to the present date.