The Hangover 2 gets a headache from Louis Vuitton lawsuit
Everyone knows Louis Vuitton takes trademark infringement pretty seriously. Just ask all the people they've sued. So it's kind of surprising Warner Brothers didn't work with the luxury goods retailer before featuring a comically faux Louis Vuitton duffle in The Hangover Part 2. Zach Galifianakis' line "Careful, that is a Louis Vuitton" became something of a catch phrase, which has further annoyed the proprietary brand.
The knock-off used in the movie was produced by the Diophy group of companies, which is also being sued by Vuitton. Vuitton claims trademark dilution, false designation of origin and unfair competition.
They obviously have a case, and a right to defend their brand and their trademark and image. But it should be taken into consideration that it's pretty strongly implied that the bag in the movie is a fake, and given that it's Galifianakis' character, the buying of fake luxury goods is painted in a derogatory light. But, LV isn't known for their sense of humor.