A trade group representing meat and poultry giants including Cargill and Smithfield Foods filed suit on Friday to stop a California measure improving animal welfare that was heralded as a "loud and clear" rebuke of factory farming when it was approved earlier this year.

Reuters first reported on the lawsuit, which was filed by the North American Meat Institute.

The industry group is asking the court to halt Proposition 12, which passed in November backed by over 60 percent of voters. Proposition 12 won praise from numerous animal welfare groups, with the ASPCA calling it at the time an "amazing victory for animals in California" and Mercy for Animals declaring it the "strongest animal welfare law for farmed animals in history."

The law, as Mercy for Animals previously explained, "outlaws the most extreme forms of animal confinement throughout the Golden State. Once it's implemented, egg-laying hens, baby calves raised for veal, and mother pigs will no longer be confined in cages. Additionally, all eggs, veal, and pork sold in the state will meet this standard."

According to the Meat Institute, however, the recent state law "exposes companies to potential criminal penalties and the threat of civil lawsuits filed by competitors and others" and violates the U.S. Constitution's Commerce Clause.

The group's president and CEO, Julie Anna Potts, asserted in a press statement Friday that Proposition 12 "hurts the family on a budget" and "unfairly punishes livestock producers outside of California by forcing them to spend millions more just to access California markets."

The suit was filed in the U.S. District Court for the Central Distict of California.