The U.S. Department of Agriculture is not complying with a federal law on labeling genetically engineered foods, alleges a lawsuit filed in northern California’s U.S. District Court in August.

The Center for Food Safety, an environmental nonprofit based in San Francisco, filed the suit, saying the U.S. Department of Agriculture has not studied “electronic and digital disclosures” (such as QR codes) for genetically engineered foods, as opposed to on-package text, as is required by the law. The GE Labeling Act went into effect in 2016.

“That study was required to be finished by July 2017, with an opportunity for public participation, but USDA never completed the study or published it for public comment,” the center said in a statement.

The GE Labeling Act requires USDA to establish federal standards for labeling by July 2018. The labeling study will inform the agency’s ultimate decision, “which is why it was required to be completed a year earlier” according to the center. “One of the most controversial aspects of the law is how it will require companies to label GE foods, and whether companies will be able to forgo clear, on-package labeling through the use of QR codes and other digital disclosures.”

According to the law, USDA can consider several options: on-package text, a GE symbol on packages, or “electronic or digital disclosures,” which would require shoppers to use a smart phone to scan packages to access a website or call a toll-free number for every single product to find out if it was produced with genetic engineering.

“Americans deserve nothing less than clear on-package labeling, the way food has always been labeled,” said George Kimbrell, legal director for the center. “Allowing companies to hide genetically engineered ingredients behind a website or QR code is discriminatory and unworkable.”