Dave Murphy came up with the idea while on a flight home to Iowa in January. After what he’d just been through, he knew it was time to go for the jugular, as it were. Murphy, founder and CEO of Food Democracy Now!, a network of more than 650,000 farmers and citizens working to fix the food system, had just spoken before a group of Monsanto shareholders at their annual meeting. As he urged investors to push the company to stop fighting labeling initiatives for genetically modified food and embrace mandatory labeling, many people in the audience didn’t even bother to turn around and listen to his speech.

This happened at the beginning of the year, not long after a group of organic and non-GMO farmers lost a lawsuit that sought protections against unwitting genetic contamination of their crops with Monsanto’s patented products, as well as the company’s “abusive patent infringement” policies. After working on the Monsanto suit for more than three years and then seeing the callousness of the company toward anyone suggesting it change its ways, Murphy decided it was time to employ a new strategy: get people and financial institutions to divest their money from the company’s stock altogether. By focusing its efforts on three banks—Vanguard, Fidelity, and State Street—Murphy says the Divest Monsanto Now! campaign can directly affect nearly 15 percent of Monsanto’s $60 billion worth of stock.

On Friday, May 9, protests will take place outside the headquarters of these financial institutions across seven cities in what is being called the Monsanto Stock Plunge (find out if there’s an event near you). Additionally, Food Democracy Now! is encouraging individuals who know they own shares in the company through one of the banks’ mutual funds to call their financial planners to request that their money be pulled from portfolios that include Monsanto.

“We want people to understand that where they invest their money is just as important as where they get their food,” Murphy says. “If you shop at a farmer’s market, pay for a CSA, or care about healthy food, you need to take the next step and put your money where your mouth is. We want the conversation on socially responsible investing to grow to a larger public awareness. Owning Monsanto is not an option.”

Divestment campaigns have been successfully implemented with other controversial industries, including tobacco and fossil fuels. On Tuesday, Stanford University became the most prominent university to completely divest from all fossil fuel companies. One of the best-known examples of divestment occurred toward the end of the apartheid era in South Africa. American activists pushed retirement funds, mutual funds, and investment institutions across the United States to sell off the stocks of companies that did business in the country.

Murphy says he’s already hearing from hundreds of people who have called their financial planners to see if their portfolios include Monsanto stock; if they do, they’re immediately selling it. The campaign is believed to be a first in the food and agriculture industry, but Murphy says it could not come at a better time, with Monsanto and other agribusinesses fighting tooth and nail against efforts to label genetically modified foods in numerous states. (Pro-labeling advocates are on something of a hot streak of late, however, with the state legislatures in Connecticut, Maine, and most recently Vermont signing mandatory labeling laws.)

“After watching Monsanto bully farmers and spend more than $13 million to defeat GMO labeling in the U.S. over the past two years, we decided that it’s time to take the gloves off and let them know that this movement is serious about regaining our basic democratic rights to know what’s in our food,” Murphy says. “Monsanto executives and companies that support them oppose mandatory labeling of GMO foods at their own peril.”