Okla. Stat. tit. 12A, § 4-207
Oklahoma Code Comment
See the Oklahoma and Official Comments to Section 3-416 . The fact that damages for breach of warranty under this Section include expenses does not now make these actions attorney's fee cases. The action is not on the instrument, so 12 O.S. §936 does not apply. Oklahoma has an affinity for the American Rule that probably will not be overcome simply by use of the word "expenses." See. Goodman v. Norman Bank of Commerce 565 P.2d 372 (Okla. 1977), over-ruled on other grounds, Reynolds-Wilson Lumber Co. V. Peoples Nat'l Bank, 699 P.2d 146 (Okla. 1985). But see Guaranty Bank & Trust Co. v. Federal Reserve Rank of Kansas City, 454 F.Supp. 488 (W.D. Okla. 1977). An agreement between the parties, however, should be able to provide for the recovery of fees and also to set the rate of interest recovery. In the absence of an agreement, the rate of interest would be set by 15 O.S. § 266.