Brown had been in the lineup for eight of the Oilers' nine games and had zero points, a minus-1 rating and 19 penalty minutes. The 5-foot-11 grinder joins a Sharks team that is 8-0-1.
"Mike plays a speed game and fits the 'Fast, Hard and Supportive' mantra that our team wants to play with," Sharks general manager Doug Wilson said in a statement. "He is a player with tremendous character, knows the Western Conference well and brings a tough, physical ingredient to our lineup."
Edmonton acquired Brown from the Toronto Maple Leafs early in the lockout-shortened 2013 season, also giving up a fourth-round pick in 2014. He had one goal in 35 games with the Oilers.
Brown, 28, is in the final season of a US$2.21-million, three-year contract. He counts $736,667 against the salary cap.