Bulley & Andrews, Inc. v. Symons Corp.
Appellate Court of Illinois
428 N.E.2d 1031 (Ill. App. Ct. 1981)
Bulley & Andrews (plaintiff) contracted with Symons (defendant) to receive concrete-forming equipment from Symons's catalog, which pictured both looped and threaded tie rods; Symons supplied threaded tie rods (rather than the looped rods Bulley typically used) and also supplied rustication strips not shown in the catalog at all, and Bulley used both without objection throughout the project. After finishing, Bulley sought reimbursement for the extra expense of the tie rods and rustication strips, Symons refused, and the trial court ruled for Symons; Bulley appealed.
Whether the parol evidence rule prohibits evidence that the parties' course of performance and conduct modified or clarified the original terms of their written contract.