Michael Phelps insists that these were his last Olympics; the latest buzz is that he may risk losing his new medal haul because of an ad campaign for Louis Vuitton.

The retired top multi-Olympic champion was accused of violating the International Olympic Committee (IOC) rules after ad pictures were found on Twitter on August 13 promoting the French luxury brand that is a non-Olympic official sponsor.

Louis Vuitton officially launched the campaign on Thursday, August 16th, but photos from the campaign were leaked on August 13th, during the last days of the 2012 Olympic Games in London. The photos were leaked breaking The IOC provision known as rule 40 adopted earlier this year. Rule 40 states "a competitor or a team may lose the benefit of any ranking obtained in relation to other events at the Olympic Games at which he or it was disqualified or excluded; in such case the medals and diplomas won by him or it shall be returned to the IOC." In other words, Phelps could theoretically be stripped of his medals from London.

The London Olympic Games ran from July 27 to August 12.

The photo of Phelps in the bathtub next to a Louis Vuitton bag, however, popped up on Paper Mag and the Los Angeles Times, among other websites.

Many Olympic athletes have spoken out against the rule, including the USA track and field team who staged a twitter protest against it. The athletes who came out against the rule claim that they should be allowed to determine how their own likeness is used during the games, and that Rule 40 hurts those athletes without big endorsement deals. The IOC claims that they need to limit advertising in order to protect their sponsors, who make the Games possible. The regulation was just introduced this year.

Middle distance runner Leo Manzano told his Facebook followers that he’d been forced to take down comments on his running shoes and their performance because of the rule. Manteo Mitchell, who became a hero of the London games by completing his leg of the 4X400 relay with a broken fibula, expressed his opposition via Twitter: “I am PROUD to represent my Country... but at the end of the day... THIS IS MY JOB!!!!!!” Both Manzano and Mitchell are sponsored by Nike. Adidas sponsored the London games.

The French fashion house said after the two photos, snapped by famed photographer Annie Leibovitz, had leaked that they were in fact unofficial images and were stolen from the company.

Phelps' management team has also denied releasing the images.

Recently, Phelps' longtime agent, Peter Carlisle, dismissed the fact that the retired swimmer may have violated International Olympic Committee rules when provocative pictures for the campaign were leaked on the Internet during the London Games.

Carlisle told The Associated Press there's no issue with the IOC because Phelps did not authorize use of the pictures, which were leaked by a source that still isn't known and appeared on several Web sites. In fact, the agent added, there are dozens of similar, unapproved uses of most top athletes' names and images during any Olympics.

Phelps won four golds and two silvers at what he insisted was his final Olympics, raising his career totals to 18 golds, two silvers and two bronzes. The 27-year-old American retired as soon as he finished his final race in Britain.