P manufactures a removable upper cooking surface, described as a 'platen,' for two-sided cookers. Part of the novelty of the invention is that the studs are welded to the back of the plate rather than bolted to it, giving the side that touches the food a smooth unpenetrated surface with no seams. This facilitates uniform Teflon coating and eliminates the accumulation of food deposits and grease in the seams on the working surface of the prior art platens. The Teflon coating eventually wears off with use. Each platen has a useful life of approximately six to twelve months before it must be replaced or refurbished. Customers often bend or break off some of the studs on the back, which must be repaired or replaced before a refurbished platen may be reused. P does not refurbish the used platens; its manufacturing techniques make it more cost-effective simply to produce new ones. D refurbishes and resells used platens. D cleans the platen by grit blasting, replaces the old Teflon coating on the cooking surface, and repairs or replaces any broken or bent studs by unbending them or by hand-welding new ones. Users send in their old platens, and D provides them with reconditioned platens for about $40 vs. P's new replacement at $90. The replacement platens from D are not the same articles that D received from the particular user. P's '775 Patent covers the platen and the method for producing it. The specification of the patent itself states that the device can be refurbished. P sued D for infringement. Both sides moved for summary judgment. The court held that D's activities were permissible repair, and granted summary judgment to D. The court noted that 'P all but admitted that cleaning, recoating, and unbending bolts does not constitute infringement' and therefore the 'case is reduced to a question of whether the replacement of one or more broken bolts from the back of the platen somehow transforms the job from the category of refurbishment and repair to reconstruction.'