Plaintiffs in a nearly $1 billion securities class action stemming from food-borne-illness outbreaks at Chipotle Mexican Grill restaurants will not get another chance to amend their lawsuit, a Manhattan-based appeals court ruled on Wednesday, ending a series of price-drop suits against the California-based food chain.

The ruling, from a three-judge panel of the U.S. Court of Appeals for the Second Circuit, upheld a trial court’s decision denying the investors’ motion to file a third amended complaint against Chipotle over the outbreaks that sickened more than 600 people in 2014 and 2015.