A group of grocery and convenience store chains, including Kroger, Walgreens, Safeway and Albertsons have filed a lawsuit claiming many of the nation’s largest egg producers, egg processors and their trade groups have engaged in a decade-long price fixing conspiracy for eggs sold to stores and restaurants nationwide, the Hoosier AG Today reported.

The grocery and c-store companies filed the suit in a Pennsylvania federal court.

The plaintiffs claim that the United Egg Producers, United Egg Association, U.S. Egg Marketers and 14 egg producers and processors agreed to reduce the supply of eggs in order to artificially increase prices. According to the lawsuit, this action resulted in a price increase of 45% on eggs between August 2007 and March 2008 to historic and unprecedented highs.