A dozen states want the U.S. Supreme Court to block a California law requiring any eggs sold there to come from hens that have space to stretch out in their cages.
The Missouri attorney general says a lawsuit will be filed Monday alleging California's law has cost consumers nationwide up to $350 million annually because of higher egg prices since it took effect in 2015.
The lawsuit claims California's requirements violate the U.S. Constitution's interstate commerce clause and are pre-empted by federal law.
A federal appeals court panel rejected similar claims last year in a separate case brought by six states. The Missouri attorney general says the new lawsuit is bolstered by an economic study.
Other plaintiffs are Alabama, Arkansas, Indiana, Iowa, Louisiana, Nebraska, Nevada, North Dakota, Oklahoma, Utah and Wisconsin.