By April 2002, with an excess of talent employed as a result of having purchased WCW and ECW, WWE needed a way to provide exposure for all of its talent. This problem was solved by introducing a "Brand Extension", with the roster split in half and the talent assigned to either Raw or SmackDown! in a mock draft lottery. Wrestlers, commentators and referees became show-exclusive, and the shows were given separate on-screen General Managers. The brand extension came into effect on April 1, 2002. Shortly thereafter, on the June 24, 2002 episode of Raw, Vince McMahon officially referred to the new era as "Ruthless Aggression". Later in 2002, after WWE Champion Brock Lesnar announced himself exclusive property of the SmackDown! brand and with the creation of the World Heavyweight Championship, all the championships became show-exclusive too. Additionally, both Raw and SmackDown! began to stage individual pay-per-view events featuring only performers from that brand - only the major four pay-per-views Royal Rumble, WrestleMania, SummerSlam and Survivor Series remained dual-branded. The practice of single-brand pay-per-view events was abandoned following WrestleMania 23. In effect, Raw and SmackDown were operated as two distinct promotions, with a draft lottery taking place each year to determine which talent was assigned to each brand. This lasted until August 2011, when the rosters were merged and the Brand Extension was quietly phased out.