Micro Cap Biotechnology
Stocks Ranked by
Market Capitalization

Micro Cap Biotechnology Stocks at a Glance

Biotechnology companies research and develop novel drugs and therapies, often with no products yet on the market. Clinical-trial readouts and regulatory decisions drive binary stock moves, making pipeline breadth, cash runway, and partnership deals the key variables.

There are 276 micro cap Biotechnology stocks — companies in the Biotechnology industry with a market cap under $250M — worth a combined $19.1B.

The largest by market cap are Sionna Therapeutics (SION) at $249M, MacroGenics (MGNX) at $242M and ProQR Therapeutics (PRQR) at $240M.

Among institutional investors, Eledon Pharmaceuticals (ELDN) drew the most net new fund positions in Q2 2026: 51 funds opened new positions, taking total fund holders up 40 (33%) quarter-over-quarter.

• Combined market cap: $19.1B across 276 stocks.
• Micro Cap: market cap under $250M.
• Largest constituent: Sionna Therapeutics (SION), $249M market cap.
• Most net new fund positions in Q2 2026: Eledon Pharmaceuticals (ELDN), +40 holders.

Market caps and prices updated daily; fund activity based on aggregated SEC 13F filings for Q2 2026.