I think it will depend on Member State law. Maize pollen escaping is supposed to be guaranteed against, but the procedures as proposed in France are laughable (insufficient distance between GM and non-GM).

Good news for attorneys in France who have experience in environmental law. I suspect that, even were the plants grown in greenhouses, pollen would escape. Ventilation is a necessity and I rather doubt that HEPA level filtering would be applied, thought double filtering through water might work. But do farmers have the equivalent to a tort process for damages in France?

As the Dutch said while fighting the Spanish: "It is not necessary to have hope in order to persevere."