Blueberry farmers in New Jersey have been waging a court battle for more than a decade against Novartis Crop Protection Inc., the maker of a pesticide known as AG600, which, they say, killed some of their plants and caused long-term damage to others.

Now, for the second time, a federal appeals court has revived the suit and declared that the lower court improperly dismissed the farmers’ state law claims as pre-empted by the Federal Insecticide, Fungicide and Rodenticide Act, or FIFRA.