The Illinois Supreme Court reversed the certification of a nationwide contract class in Avery v. State Farm Mutual Auto Ins. Co., No. 91404 ( Ill. August 18, 2005), the $1.06 billion suit over the use of aftermarket auto parts.

The suit was originally filed in 1998 when plaintiffs claimed that the use of non-Original Equipment Manufacturer (OEM) parts in repairing damaged vehicles constituted a breach of contract between State Farm and its insureds. Plaintiffs contended that State Farm's standard contract promised to “restore policyholders' cars to their pre-loss condition by using parts of like kind and quality,” and the use of non-OEM parts violated that contract provision.