National Lockwasher Co. v. George K. Garrett Co., 137 F.2d 255 (3d Cir. 1943), is one of the earliest or the earliest federal court decision to hold that it is patent misuse for a patentee to require licensees not to use a competitive technology. Such provisions are known as "tie-outs." Background National Lockwasher owned U.S. Patent 1,655,018, which covered split-ring, compression-spring lock washers with a construction preventing them from interlinking with one another when handled in bulk. The washer accomplishes this by making the helical ring-shaped washer extend more than 360 degrees in circumference, cutting the ends of the washer so that the end faces make an angle with the top and bottom faces of the washer, and making the spaces between the ends of the washer smaller than the thickness of the washer stock but large enough to allow compression to flatten the washer. (If the space is smaller than the thickness (cross-section height) of the washer stock, one washer cannot pass through the end space of another washer and entangle it.) A lock washer is used to prevent a screw, bolt, or nut from loosening under vibration. It operates as a spring under compression having sufficient elasticity to neutralize the play between the assembled parts that vibration causes. National licensed five other washer manufacturers under the patent. Each license "contained a provision to the effect that the licensee agrees, while the agreement is in force, that it will not manufacture any other form of non-tangling spring washers except those covered by the patent in suit." There are other forms of non-tangling spring washers on the market, which use different technology from that of the patent. The district court found that Garrett infringed the patent, that it was valid, and directed an accounting. A judgment of $18,000 was entered. Garrett appealed to the court of appeals. Ruling of Third Circuit "So what we have here," the court said, "is a patentee who gives a license to a manufacturer for a stipulated consideration, part of the consideration being that the licensee will abstain from manufacturing any other kind of nontangling spring washer except those covered by the license." The court recognized that this case was different on its facts from the Supreme Court's prior tie-in patent misuse cases such as Morton Salt Co. v. G.S. Suppiger Co., in which the Court held that a patentee "may not claim protection of