Legislation has been introduced in Congress that would overturn California’s Prop 12. But Reuters reports some of the country’s biggest pork producers who’ve already spent money to comply with the California requirements don’t favor throwing out Prop 12. The Ending Agricultural Trade Suppression Act would curb states’ ability to regulate agricultural products sold within their borders.

Clements Food Group, the fifth-largest pork processor in the country, says it won’t support the EATS Act. Some of the larger producers in the country like Tyson Foods and Smithfield have said publicly that they’ll be complying with the law when it takes effect on January 1. Prop 12 bans sales within California of pork, veal, and eggs from animals whose housing conditions fail to meet certain standards.

The bill is supported by the National Pork Producers Council.