In the filing in state Supreme Court in Manhattan, plaintiff Justin Henry says he was never paid for the office work he performed from October 2007 through May 2008 but should have been under state labor law.
The suit alleges there was no academic or vocational training as part of the internship, and that employees would have needed to be hired to do the work if Henry wasn't doing it for free. The suit claims Henry routinely worked more than 40 hours a week, but never got any overtime wages.
Atlantic is part of Warner Music Group. Warner declined to comment on pending litigation.
Although Henry is the only plaintiff, attorney Maurice Pianko said it was filed as a class-action suit because there could be others in the same position who decide to join.
Similar lawsuits over unpaid internships have been filed in other industries.
In one lawsuit filed last week, two former interns who worked at W Magazine and The New Yorker sued parent company Conde Nast Publications for allegedly failing to pay them the minimum wage. Another lawsuit has been filed against Hearst Magazines.
A federal judge last week ruled in a case over unpaid internships in the film industry. U.S. District Judge William H. Pauley III ruled that Fox Searchlight Pictures violated minimum wage and overtime laws by not paying interns who worked on production of the 2010 movie "Black Swan."
In the ruling, Pauley said Fox should have paid the two interns who filed the lawsuit because they did the same work as regular employees, provided value to the company and performed low-level tasks that didn't require any specialized training.