For several years, the five-store San Diego–based natural food chain Jimbo’s Naturally has refused to bring in new products that contain at-risk ingredients if they aren’t non-GMO verified. Plus, Jimbo’s has stopped promoting GMO products already on its shelves. Now the stores are down to just a few GMO holdouts, and owner Jim Someck says the operation is taking the final step: “As we go through each [product type], we are starting to eliminate those products that have been grandfathered in, if we have a suitable replacement.” Even for those that don’t, he hopes to eliminate most, if not all of them, within the next year.

In March 2013, Dean Nelson, owner of Dean’s Natural Food Markets, with three New Jersey locations, set a similar policy: Although current products are grandfathered in, no new products can be introduced that contain ingredients at high risk of being genetically engineered, such as corn, soy, and canola, unless those products are non-GMO verified.

Nelson says he expects his stores will eventually start discontinuing products already on their shelves with at-risk ingredients, but adds, “It’s a slow process.” In the meantime, the stores’ current policy attracts local shoppers, and it has inspired some vendors to get their products non-GMO verified. That has made Nelson’s job easier: “Now, we just say, ‘If it is not non-GMO verified, it can’t come in.’ That’s actually a blessing.”

Instead of pushing customers away, Someck says the policy has actually inspired increased store patronage. “What it has done, even though it wasn’t intended, is build up a lot of loyalty in our stance and what we believe in,” he says. “I didn’t make this stand because I thought it was going to be financially successful. I did it because that’s who we are.”