Samuel Caster

Samuel Caster is an American businessman who founded Mannatech, a multi-level marketing firm located in Coppell, Texas. Prior to founding Mannatech, Caster had founded and run Eagle Shield and marketed Electracat, a pest control device declared by the Attorney General of Texas as a hoax. He now runs Alovea and Manna-Relief.

Early life Caster attended North Texas State University (now University of North Texas) for a four-month period in 1972. Caster agreed to stop making statements about Eagle Shield. In October 2007, it was reported that the company had fired Grant Thornton LLP as its auditor after the accounting firm demanded that Mannatech remove Caster from all responsibilities.