Soleno Therapeutics (SLNO) had the highest return in September 2023 by a mid-cap US stock, returning 495%.

ASSET	MONTH	% RETURN
Soleno Therapeutics (SLNO)	September 2023	494.96%
Crinetics Pharmaceuticals (CRNX)	September 2023	69.94%
Immunovant (IMVT)	September 2023	67.42%
Ramaco Resources (METC)	September 2023	40%
Warrior Met Coal (HCC)	September 2023	27%
Alpha Metallurgical Resources (AMR)	September 2023	26.12%
TAL Education (TAL)	September 2023	24.62%
CCC Intelligent Solutions Holdings Inc Common Stock (CCCS)	September 2023	24.3%
Trump Media & Technology (DJTWW)	September 2023	22.19%
Mirum Pharmaceuticals (MIRM)	September 2023	19.29%
Cidara Therapeutics (CDTX)	September 2023	19.09%
Peabody Energy (BTU)	September 2023	18.14%
VEON (VEON)	September 2023	17.97%
Alignment Healthcare LLC (ALHC)	September 2023	17.83%
Uranium Energy (UEC)	September 2023	17.58%
Rev (REVG)	September 2023	17.5%
Centrus Energy (LEU)	September 2023	17.15%
Denison Mines (DNN)	September 2023	15.38%
Liberty Oilfield Services (LBRT)	September 2023	14.22%
Energy Fuels (UUUU)	September 2023	13.85%
Scholar Rock (SRRK)	September 2023	13.42%
Alliance Resource Partners (ARLP)	September 2023	12.43%
Hafnia (HAFN)	September 2023	12.14%
FirstCash (FCFS)	September 2023	11.96%
NexGen Energy (NXE)	September 2023	11.8%

Mid-cap stocks are treated as having a market cap between $2B and $10B.