Clark Foam was a Californian company that manufactured surfboard blanks — foam slabs, reinforced with one or more wooden strips or "stringers" — cast in the rough shape of a surfboard and used by surfboard shapers to create finished surfboards. Founded in 1961 by Gordon "Grubby" Clark, Clark Foam established a near-monopoly on the American market, and a strong presence in the international market, which it held until the company's unexpected closure in 2005.