Allegheny Technologies (ATI) had the highest return in July 2016 by a large-cap US stock, returning 39.9%.

ASSET	MONTH	% RETURN
Allegheny Technologies (ATI)	July 2016	39.91%
Coeur Mining (CDE)	July 2016	38.52%
Somnigroup International (SGI)	July 2016	36.3%
ArcelorMittal SA ADR (MT)	July 2016	35.83%
Advanced Micro Devices (AMD)	July 2016	34.77%
eBay (EBAY)	July 2016	32.99%
TTM Technologies (TTMI)	July 2016	32.67%
Seagate Technology (STX)	July 2016	32.3%
Gerdau SA ADR (GGB)	July 2016	29.68%
Biomarin Pharmaceutical (BMRN)	July 2016	28.14%
Garmin (GRMN)	July 2016	28.05%
FTAI Aviation (FTAI)	July 2016	27%
HubSpot (HUBS)	July 2016	25.9%
Penske Automotive (PAG)	July 2016	25.62%
Lumentum (LITE)	July 2016	24.95%
STMicroelectronics NV ADR (STM)	July 2016	24.7%
IES (IESC)	July 2016	24.7%
Nomura Holdings Inc ADR (NMR)	July 2016	24.51%
Cemex SAB de CV ADR (CX)	July 2016	24.19%
Alnylam Pharmaceuticals (ALNY)	July 2016	23.78%
Marvell Technology (MRVL)	July 2016	23.68%
Ares Management (ARES)	July 2016	23.4%
Logitech International (LOGI)	July 2016	23.31%
State Street (STT)	July 2016	22.77%
NVIDIA (NVDA)	July 2016	22.13%

Large-cap stocks are treated as having a market cap of $10B+.