P3 Health Partners (PIII) had the highest return on May 21 by a small-cap US stock, returning 37.1%.

ASSET	DATE	% RETURN
P3 Health Partners (PIII)	5/21/2026	37.09%
Falcon's Beyond Global, Inc Class A Common Stock (FBYD)	5/21/2026	36.62%
FuelCell Energy (FCEL)	5/21/2026	32.5%
WhiteFiber, Inc Ordinary Shares (WYFI)	5/21/2026	20.37%
Entravision Communications (EVC)	5/21/2026	16.28%
Ballard Power Systems (BLDP)	5/21/2026	16.03%
Plug Power (PLUG)	5/21/2026	15.95%
Eos Energy Enterprises (EOSE)	5/21/2026	15.07%
Regenxbio (RGNX)	5/21/2026	14.6%
Galectin Therapeutics (GALT)	5/21/2026	14.55%
QuantumSi (QSI)	5/21/2026	13.79%
Hovnanian Enterprises (HOV)	5/21/2026	13.46%
Quantum (QMCO)	5/21/2026	12.97%
Claritev (CTEV)	5/21/2026	12.52%
Advantage Solutions (ADV)	5/21/2026	12.36%
SolarEdge Technologies (SEDG)	5/21/2026	12.34%
Lightwave Logic (LWLG)	5/21/2026	12.28%
SEALSQ (LAES)	5/21/2026	11.99%
SharonAI Holdings, Inc Class A Common Stock (SHAZ)	5/21/2026	11.87%
Virgin Galactic (SPCE)	5/21/2026	11.79%
Bitdeer Technologies Group Class A Ordinary Shares (BTDR)	5/21/2026	11.68%
Aehr Test Systems (AEHR)	5/21/2026	11.36%
Certara (CERT)	5/21/2026	11.18%
Rackspace Technology (RXT)	5/21/2026	11.03%
Lumexa Imaging Holdings, Inc Common Stock (LMRI)	5/21/2026	10.99%

Small-cap stocks are treated as having a market cap between $300M and $2B.