Proposition 12 took effect in California on January 1st, where National Pork Producers Council (NPPC) says the impacts will be seen as early as this week. Widely referred to as Prop 12, the new regulation requires egg-laying hens, calves raised for veal and breeding pigs to be able to move around (lie down, stand up and turn around) without touching the sides of the stall or another animal. While most sows are housed in individual pens, Prop 12 states they must have at least 24 square feet of space, which would require large group pens.

As California only produces about 8,000 sows, the state demands production of roughly 700,000 sows – which is met through states like Iowa, Minnesota and other Midwestern states. Of those high-production states, only 4% or 5% is currently compliant with the legislation. Critics of the legislation believe Californians didn’t fully understand the effects of what they were voting on. NPPC and the American Farm Bureau have filed a joint petition, to be addressed by the Supreme Court on Friday.

Read more on Prop 12 here.