Right, regardless of the name on the side there's only 8 companies that actually manufacture AR 15 lowers. The following list shows the makers and what brand name they are sold under. This list is a few years old now so there may be new makers that aren't shown.
Lewis Machine & Tool.............................................. ..................................................
LMT
Lauer
DS Arms
PWA
Eagle
Armalite
Knights Armament
Barrett
Continental Machine Tool.............................................. ...............................................
Stag
RRA
HS
Noveske
Century
Global Tactical
CLE
S&W
MGI
Wilson Tactical
Grenadier Precision
Colt
LAR Manufacturing..................................... .................................................. .............
LAR
Bushmaster
Ameetec
DPMS
CMMG
Double Star
Fulton Armory
Spikes Tactical
JVP............................................... .................................................. ..........................
Double Star
LBR
Mega Machine Shop.............................................. .................................................. ...
Mega
GSE
Dalphon
POFicon
Alexander Arms
Olympic........................................... .................................................. ......................
Olympic
SGW
TROMIX
Palmetto
Dalphon
Frankford
Sun Devil............................................. .................................................. ..................
Sun Devil
Superior.......................................... .................................................. ........................
Superior