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Specialist Hedge Fund Conviction in Biotech

Topic:

Positioning

Sector:

Biotechnology

Author:

Sam Pierson

September 9, 2026

Healthcare specialist funds underwrite clinical and regulatory risk that generalists can't, and their positions are public in SEC filings. S3 maps those filings to its Healthcare Cohort, a curated list of dedicated healthcare managers and one of eleven proprietary hedge fund cohorts. We sort U.S. biotech stocks into quintiles by Healthcare Cohort holder count, rebalanced monthly from February 2015 through June 2026.

The most-specialist-owned quintile returned +19.5% annualized against −2.9% for the least-owned; a long-short book on the spread posted 0.95 return/volatility with a −25% maximum monthly drawdown. The signal survives transaction costs, borrow costs and a hard borrow constraint. This report covers methodology, drawdowns, the top-20 specialist longs ahead of the June rally, and a shift in short interest that changes how a bearish SI screen should be read. ⠀

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¹ S3 Partners is not affiliated with Verdad. The Verdad research paper referenced above did not rely on S3 data. ⠀

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