Genmab A-S (GMAB) had the highest return between 2012 and 2015 by a large-cap US stock, returning 1,949.2%.

ASSET	YEARS	% RETURN
Genmab A-S (GMAB)	2012-2015	1,949.24%
Netflix (NFLX)	2012-2015	1,039.24%
Alnylam Pharmaceuticals (ALNY)	2012-2015	1,030.13%
Regeneron Pharmaceuticals (REGN)	2012-2015	860.66%
Canadian Pacific Railway (CP)	2012-2015	851.21%
DexCom (DXCM)	2012-2015	760.29%
Tesla (TSLA)	2012-2015	729.35%
Incyte (INCY)	2012-2015	620.6%
Constellation Brands Inc Class A (STZ)	2012-2015	584.7%
Neurocrine Biosciences (NBIX)	2012-2015	547.25%
Manhattan Associates (MANH)	2012-2015	541.65%
Delta Air Lines (DAL)	2012-2015	530.18%
Illumina (ILMN)	2012-2015	519.19%
Insmed (INSM)	2012-2015	481.73%
EPAM Systems (EPAM)	2012-2015	471.78%
Tyler Technologies (TYL)	2012-2015	464.69%
NXP Semiconductors (NXPI)	2012-2015	433.9%
Booz Allen Hamilton (BAH)	2012-2015	432.29%
Builders FirstSource (BLDR)	2012-2015	427.62%
Broadcom (AVGO)	2012-2015	426.35%
Southwest Airlines (LUV)	2012-2015	407.17%
Gilead Sciences (GILD)	2012-2015	393.95%
Corpay (CPAY)	2012-2015	376.91%
Skyworks Solutions (SWKS)	2012-2015	361.99%
U-Haul (UHAL)	2012-2015	354.88%

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