GMO Inside, a campaign nation-leading green economy organization Green America, launched a new campaign aimed at pressuring Starbucks to use only organic milk sourced from cows not fed GMOs. The group is calling on Starbucks to use a third-party verifier to ensure that milk is truly being sourced from non-GMO fed cows.

“Starbucks already serves soy milk that is organic and non-GMO. Consumers also deserve dairy milk held to the same standard and level of quality,” says Nicole McCann, campaign director for GMO Inside. “Consumers will put pressure on Starbucks to serve only organic, non-GMO milk. And the reality is that the process Starbucks put in place to remove rBGH from its milk source can be used to source organic milk.

A request for comment from Starbucks was not immediately returned.