Diamond Shamrock

1967-2001
Diamond Shamrock Started In 1967 When Shamrock Oil And Diamond Alkali Merged

2001-present
Valero Bought Diamond Shamrock In 2001, And Diamond Shamrock Changed Its Logo For The Red Bar To Be On The Top And The Green Diamonds On The Bottom, Most Diamond Shamrock Stations Were Turned Into The Valero Brand In 2005, As Of July 2013 Some Of The Diamond Shamrock Stations Still Survive, Valero Brought Shamrock Oil Back After A 33 Year Absence