The court then has to determine whether the copied material replaces the market for the original, what percentage of the whole is reproduced and what effect it will have on the market for the original.
Much of copyright law is a legal gray area. Some creative types argue that the law favors some media over others. Fashion designers can't copyright the shapes or style of a dress because it's deemed "functional" but they can copyright an image on a t-shirt.
There have been just a handful of copyright lawsuits pertaining specifically to celebrities and their tattoos.
Basketball player Rasheed Wallace and Nike were sued by the athlete's tattoo artist, when the ink was outlined in a television commercial while he talked about it. The suit was settled.
That same year, soccer star David Beckham and his artist Louis Molloy got into a tiff over whether Beckham's tats would feature prominently in an ad campaign
"I own Beck's tattoo .. and I'll sue," Molloy said at the time.