Mannatech, Incorporated, is a multinational multi-level marketing firm engaged in research, development, and distribution of "glyconutrients," the company's name for blends of plant-sourced saccharides. Mannatech was founded in November 1993 by Samuel L. Caster and is headquartered in Coppell, Texas. It operates in 24 countries, including the United States, Canada, Australia, countries in Asia, Africa, and within the EU.