takes issue only with the district court’s treatment of the former two.
An award of attorney fees is within the discretion of the district judge. Orthopedic Equipment Co. v. All Orthopedic Appliances, 707 F.2d 1376, 1384, 217 USPQ 1281, 1287 (Fed.Cir.1983). Only after the prevailing party has established the exceptional nature of the case by clear and convincing evidence should the district court decide whether or not to make the award. Reactive Metals & Alloys Corp. v. ESM, Inc., 769 F.2d 1578, 1582 (Fed.Cir.1985). On appeal, this court will review the factual underpinnings made by the district court in deciding that the case is “exceptional” under the clearly erroneous standard. We “must also be satisfied that the correct legal standard was applied by the district court in reaching its conclusion.” Id., at 1583 (emphasis in original); See also Hycor Corp. v. Schlueter Co., 740 F.2d 1529, 1538-39, 222 USPQ 553, 560 (Fed.Cir.1984). In the current appeal, appellants do not question the district court’s findings of fact, but instead challenge the propriety of the legal standard applied in deciding that this case is exceptional.
From early on, federal courts refused to adopt the “English rule” requiring the assessment of attorney fees against a losing party. Under the “American rule,” the prevailing litigant is ordinarily not entitled to any attorney fees, absent statutory authority. Alyeska Pipeline Service Co. v. Wilderness Society, 421 U.S. 240, 247, 95 S.Ct. 1612, 1616, 44 L.Ed.2d 141 (1975). A rationale for this rule is that one should not be penalized for merely defending or prosecuting a lawsuit. Fleischmann Distilling Corp. v. Maier Brewing Co., 386 U.S. 714, 718, 87 S.Ct. 1404, 1407, 18 L.Ed.2d 475, 153 USPQ 432, 433 (1967).
In patent cases, the American rule was strictly followed until 1946 when Congress amended the then patent remedy statute, R.S. § 4921, to provide that the “court may in its discretion award reasonable attorney fees to the prevailing party.” Patent Act of August 1, 1946, § 1, 60 Stat. 778, 35 U.S.C. § 70 (1946 ed.). This statute was construed to allow the award of fees in extraordinary cases when there was:
a finding of unfairness or bad faith in the conduct of the losing party, or some other equitable consideration of similar force, which makes it grossly unjust that the winner of the particular law suit be left to bear the burden of his counsel fees which prevailing litigants normally bear.
Park-in Theatres, Inc. v. Perkins, 190 F.2d 137, 142, 90 USPQ 163, 167 (9th Cir.1951).
The 1952 Patent Act incorporated this section, omitting explicit reference to the court’s discretion, but adding the words “may” and “exceptional.” 35 U.S.C. § 285, supra. However, the Reviser’s Note for § 285 indicates that no change in meaning was intended:
This section is substantially the same as corresponding provision in R.S. 4921, ‘in exceptional cases’ has been added as expressing the intention of the present statute as shown by its legislative history and as interpreted by the courts.
S.Rep. No. 1979, 82nd Cong., 2d Sess. (1952), reprinted in 1952 U.S.Code Cong. & Ad.News 2394, 2423. See generally Rohm & Haas Co. v. Crystal Chem. Co., 736 F.2d 688, 222 USPQ 97 (Fed.Cir.), cert. denied, — U.S. —, 105 S.Ct. 172, 83 L.Ed.2d 107 (1984) (in-depth summary of the relevant legislative history of the attorney fees section in the 1946 and 1952 Acts).
Allowance of fees only in exceptional cases is based on the premise that courts should attempt to strike a balance between the interest of the patentee in protecting his statutory rights and the interest of the public in confining such rights to their legal limits. A. Ahert, Attorney’s Fees: The Patent Experience, 57 J.Pat.Off. Soc’y 608, 614 (1975).
Appellants (the patentees here) argue that the balance generally weighs more heavily in favor of patentees and that a higher standard exists when an accused infringer seeks to collect fees. As support for this assertion, they say that a patent is presumptively valid, and therefore a pat