Stephen Lough (plaintiff) was a repairman at a boat dealership in Florida. Lough noticed that for stern drives, a type of propulsion device for boats, the seal assembly often became corroded. In 1986, Lough designed a new seal assembly that would prevent corrosion and created six prototypes of this assembly. He used one of these prototypes for his own boat, gave away four others to friends, and he installed the final prototype in a customer’s boat. Lough did not follow up with his friends to learn whether they were satisfied with his improved seal assembly or to get feedback of any kind, nor did he have further contact with his customer. More than a year after Lough gave out his prototypes, on June 6, 1988, he successfully applied for a patent for his seal assembly. Brunswick Corp. (Brunswick) (defendant) saw Lough’s invention and redesigned its own stern-drive seal assembly accordingly. Brunswick then began selling boats featuring the new design. Lough sued Brunswick for patent infringement. Brunswick filed a counterclaim against Lough, seeking a declaratory judgment that Lough’s patent was invalid or unenforceable. Brunswick argued that Lough’s invention was in public use more than one year before Lough filed for his patent. The jury found for Lough and awarded Lough $1.5 million in lost profits. Brunswick moved for judgment as a matter of law, but the district court denied the motion. Brunswick appealed.