Aiming at the problem that pirate products may have the same quality and prices with the genuine products in real life, this paper uses the optimization method of the game theory to establish a two-stage Stackelberg output game model composed of the genuine manufacturer, the pirate manufacturer and the government in the information market, analyzes the market equilibriums when the genuine manufacturer adopts different anti-replication strategies, and studies the government's optimal supervision policy and the genuine manufacturer's strategy choice under the circumstances where the social welfare is maximized. The research indicates that the relationship between the genuine manufacturer and government's anti-piracy efforts is like a game, in which when the genuine manufacturer toughly prevents the pirate manufacturer from entering the market, the government will choose to free-ride or slacken the supervision, but when the genuine manufacturer chooses to tolerate the pirate action moderately, the government will actively strengthen the supervision. As a genuine manufacturer, it is always beneficial to take the anti-replication strategy. And the government should encourage genuine manufacturers to reinforce their anti-replication technology and strengthen their cooperation with the genuine manufacturer to fight against piracy.