The base value of the deal is about $10.05 million, fully guaranteed. The contract includes a standard team option for a fifth year.
Rookies reported Monday. Training camp begins Thursday in Cortland, N.Y.
Richardson was the 13th overall pick in the draft, which the Jets acquired from the Tampa Bay Buccaneers in exchange for cornerback Darrelle Revis.
Source: Rich Cimini, ESPN New York