Gregg Ruth & Co. is a privately owned, Malibu, California-based jewelry design and manufacturing company founded in 1981. With over 600 bench jewelers and 750 new styles per year, CEO Gregg Ruth brings a defining vision and synergy to diamond, gemstone and bridal collections of couture jewelry. His strong focus on craftsmanship and detail is essential for the company.s elegant, sophisticated styles, which incorporate unusual diamond cuts, fancy colored diamonds, and patented setting techniques.