The IOC and London Olympic organizing committee have gone to great lengths to protect their official sponsors from outside competition, but Dr. Dre appears to have circumvented these regulations with an ambush marketing campaign for his Beats headphones. As the Guardian reports, Beats representatives have been handing out specially branded headphones to select athletes, despite the fact that the IOC prohibits non-official sponsors from advertising around the Olympics.

Thus far, Beats products have been spotted on a number of highly visible athletes, including swimmer Michael Phelps, who wears a pair of Beats-branded noise-canceling headphones before races. The company achieved a similar coup in 2008, when it gave a pair of headphones to LeBron James, who proceeded to hand them out to the rest of his US teammates.

Word of this year's campaign first leaked when British tennis player Laura Robson tweeted about receiving a pair of Beats headphones with a Union Jack design. Robson subsequently deleted her tweet, as did UK soccer player Jack Butland, who wrote "Love my GB Beats by Dre," before promptly removing the post. Butland also told a teammate, via Twitter, that Beats representatives were "bumping into" athletes around the area, though that tweet was eventually deleted as well — likely because the IOC's code of conduct prohibits athletes from promoting their personal sponsors on social media.

The Independent's Samuel Muston, meanwhile, says he recently attended an invitation-only Beats party in Shoreditch, where he saw other British athletes walking away with free headphones. At this point, however, there's no indication that Beats has paid any athlete to use or endorse its products. Neither the IOC nor the London 2012 committee have weighed in on the company's campaign, though they likely won't be thrilled about it — nor, for that matter, will Panasonic, which is an official Olympic sponsor.

Update: Despite the fact that Michael Phelps has been seen wearings Beats Audio headphones in the past, a number of reports indicate that he's been wearing Sol Republic headphones as of late.