US patent litigation is governed by what is known as the American Rule. The American Rule is that attorney fees are not awardable to the winning party (that is, each litigant must pay his own attorney fees) unless statutorily or contractually authorized. In patent infringement litigation, Section 285 of the Patent Act provides the statutory exception but only in exceptional cases. It states that the "court in exceptional cases may award reasonable attorney fees to the prevailing party". An award of attorneys' fees under Section 285, however, is only available in "limited circumstances" and "is an exception to the American Rule" (Forest Labs, Inc v Abbott Labs, 339 F3d 1324, 1329 (Fed Cir 2003)).