The Fish wasn't the first split-tailed board, nor was it the first twin-fin. Both of these designs had been done in balsa as far back as Bob Simmons' and even Tom Blake's time. In fact, ultra-short twin-fins were already making the rounds in the very early '60s, before Steve Lis is credited with combining both the split tail (swallow) and the twin-fin into what came to be known as the "Fish."
Tom Blake was a larger-than-life surf pioneer, a seminal force in the history of the sport, who almost single-handedly transformed surfing from a primitive Polynesian curiosity into a 20th century lifestyle. In the process, he was responsible for preserving much of surfing's oral history as well as resurrecting the streamlined surfboards of ancient times.
Bob Simmons - Split or twin pin tail inventor
Bear Mirandon with Simmons inspired twin pin surfboard
Bob Simmons is remembered as the man who introduced the foam-and-fiberglass surfboard and popularized the use of skegs on surfboards. He also introduced the first twin pin tail with one fin on each rail.
Steve Lis was born in San Diego in 1951. He was raised in San Diego, and started surfing at the age of 10 in 1961. He shaped and designed a stumpy, blunt-nosed kneeboard in his family garage in 1967. The 5'4" kneeboard featured flat-rocker with a split tail with twin fins. This design was called “the fish.”
Bob Simmons twin and Steve Lis twin Fish