"Mercy For Animals" took undercover video at a California egg producer and it, in part, prompted voters in 2008 to approve more humane conditions for hens. The law essentially bans cages so small the crammed animals can't turn around.
Gov. Arnold Schwarzenegger's signature extends those same rules to out-of-state farmers who ship their eggs into the Golden State, beginning in 2015 -- the same time California's law kicks in.
The Humane Society pushed the anti-cruelty measure and says this will also improve food safety, which is compromised when chickens live in stress.
"It causes their immunity to be reduced and their ability to ward off illness. That does end up creating a higher risk for consumers down the line," says Jennifer Fearing from the Humane Society of the United States.
California is the fifth largest egg producer in the country and the new regulation puts competitors on an even playing field.
However, the egg industry says studies are mixed as to whether a change in living conditions actually affects egg quality.
The U.C. Agricultural Issues Center estimates prices will increase by a couple of cents per egg because cage-free environments are more expensive. About 97 percent of consumers today choose regular eggs, while only 3 percent buy cage-free eggs.
"This a product that just about everybody eats and almost everybody chooses to eat, eggs raised with hens in cages; and we take that product and make it illegal and that's a bit of a puzzle," says professor Daniel Sumner, Ph.D., from the U.C. Agricultural Issues Center.
Shoppers ABC7 spoke with seemed okay with being forced to buy cage-free eggs.
"According to the egg producers, it'll up their overhead. Of course, they're going to pass it on to the consumer," says consumer Robert Tatum. "I'm okay with that."
"I usually tend to be more for the animals as it is anyway, whether it's chickens or dogs," says consumer Amber Williams.
Egg producers who violate the new regulations could spend six months in jail and face a $1,000 fine.