The U.S. Supreme Court denied a petition by Missouri to hear a case against California by six states.
Led by Missouri, the states sought to overturn a California law setting requirements for housing egg-laying hens.
California voters approved the law in 2008, but Missouri, along with Nebraska, Oklahoma, Alabama, Kentucky and Iowa challenged the law.
In 2015, the American Farm Bureau Federation said the law would have detrimental effects on the national egg market since California accounts for every one in eight eggs sold in the nation.
Compliance costs were estimated to cost between $25 and $30 per hen at the time.
The ruling reaffirms a November 2016 9th Circuit Court of Appeals decision against the challenge, as well.
