At the 2012 Summer Olympics in London, Feigen swam for the second-place U.S. team in the preliminary heats of the 4×100-meter freestyle relay and earned a silver medal when the U.S. team placed second in the final. Teaming with Matt Grevers, Ricky Berens and Jason Lezak, Feigen swam the lead off leg and recorded a time of 48.49 seconds.