Initiative 522, which would require labeling on genetically modified foods in Washington state, has drawn negative attention from many of the nation’s largest and most recognizable food manufacturers, including Pepsi, Coca-Cola, and Nestle.

Pepsi is the biggest contributor to the effort to oppose the initiative, with its contributions accounting for $1.6 million of the $7.2 million total contributions collected to date.

Voters will decide the issue on November 5, with the election marking one of the most expensive initiative battles in the history of Washington state.