There's a three month trial period https://investigacion.udca.edu.co/divalproex-webmd-2d3d.pdf divalproex webmd
  USDA and GMO proponents have said biotech and non-biotech crops can co-exist successfully. But opponents said the incident in Washington state shows that non-GMO farmers have to bear the burden and cost of any lost sales if their crops get contaminated, even at low levels.