U.S. rapper Dr. Dre has "succeeded with an ambush marketing operation" at the London Games aimed at Great Britain athletes without the knowledge of the British Olympic Association, according to Charles Sale of the London DAILY MAIL. Despite the IOC cracking down on rules regarding non-rights holders' advertising around the Olympics, Dr. Dre's "popular brand of Beats headphones customised with Union flag colours have been delivered" to members of Team GB. The "distinctive headphones" have been worn by several British swimmers as they have been introduced before their races at the Aquatics Center, thereby "gaining maximum exposure on the BBC." Diver Tom Daley was on screen wearing his Beats ahead of competition on Monday. This "targeting of Team GB comes on the same day the IOC confirmed Rule 40 in the Olympic charter," which forbids athletes from promoting any personal sponsors on social media during the Games unless they are official Olympic sponsors (DAILY MAIL, 7/30). In London, Mark Sweney noted tennis player Laura Robson "tweeted about receiving her headphones," although it now appears to have been removed from her account. Team GB goalkeeper Jack Butland tweeted: "Love my GB Beats by Dre." Butland had revealed in a message to Team GB footballer Karen Carney that a Beats representative "visited the team hotel on Monday." He tweeted: "They are around, I'm sure they'll bump into you guys soon." The "stunt is unlikely to go down well with legal advisors" at LOCOG or the IOC, who have strict rules against ambush marketing, to "protect official sponsors who have paid tens of millions of pounds" for their exclusive rights. The official sponsor that is "most likely to feel most aggrieved by the stunt is Panasonic." The IOC's ambush marketing initiative comes just after a protest -- initiated by U.S. athletes, including 400m sprinter Sanya Richards-Ross -- criticizing Rule 40 (GUARDIAN, 7/31). MARKETING WEEK's Sebastian Joseph wrote the amount of protection for Olympic sponsors "from ambush stunts has been a major talking point of the event so far," with some legal experts saying that the "laws are too strict." Last week, brands including brewer Brewdog and off-license chain Oddbins "launched campaigns criticising the rules" (MARKETING WEEK, 7/31).