P sued D alleging negligence and breach of warranty related to livestock milking equipment manufactured by D, distributed by Surge and installed by Carrier. D removed the case to federal court on diversity. P claims he equipment caused electric current to come into contact with the livestock during the milking operations. Carrier undertook to modify and correct the defect but abandoned its efforts without having corrected the problem. D moved to join Surge and Carrier as defendants. Joining would destroy diversity and require a remand to state court. D objected claiming that P's sole motive was to compel remand.