There's something fishy about these restaurants, but it's not suspicious in any way. after first tasting a fish taco in san felipe, mexico, ralph rubio returned to san diego to hand-craft his own recipe and introduced america to the fish taco. since that day back in 1983, ralph, with the help of a lot of great people, has sold more than 170 million fish tacos! rubio's is still based out of sunny san diego, though they operate over 190 restaurants on the west coast. investment firm mill road capital took the company private in 2010.