A proposal that would require labels on foods containing genetically modified ingredients is on track to go before California voters, and the biotechnology industry is already pushing back. Last week, a group called California Right to Know delivered nearly one million signatures to state officials, well in excess of the roughly half-million required for a statewide referendum. If the signatures are verified, the measure will go before voters in November, reports the St. Louis Post-Dispatch.

“Today we celebrate that almost a million people have spoken up in California,” says Albert Straus CQ, who runs an organic dairy in northern California. “I believe people have the right to know where their food comes from, and if this initiative succeeds in November, we’ll take a big step toward that.”

But the grocery and biotechnology industries have started a formal campaign to push against the measure, saying labels would drive up food prices and open the door for lawsuits against farmers. Last week, a group backed by the biotechnology and grocery industries, called Stop the Costly Food Labeling Proposition, formed in anticipation of the labeling initiative. Monsanto, the world’s largest producer of genetically modified seed, said it supports the group, calling potential labels misleading and expensive.

Earlier this year, the Washington-based Center for Food Safety submitted a petition with 1.1 million signatures to the U.S. Food and Drug Administration, calling for mandatory nationwide labeling. The agency is reviewing the petition and has so far counted 900,000 signatures, according to Gary Hirshberg, chairman of Stonyfield Farms, and co-founder of the national Just Label It! Campaign.

Proposals in 19 states have also called for similar requirements, but those have yet to gain much traction with lawmakers. Lawmakers in Vermont, where a labeling measure was voted out of committee, said the measure could only pass if California voters approved their own labeling law first.