Part of protecting such a technology means the lawyers must scrutinize and challenge any imitators. They’ve collected more than 5,000 pairs of shoes over three decades, Cornwell said. Sometimes, they must saw the shoes in half.

“It is more than a closet or a pile of shoes,” Cornwell said.

The collection has arrived at the law office in all manner of ways. The lawyers get to keep the prototypes, which remain confidential, as well as the size 9 men’s sample pairs, which fit Cornwell’s feet. When Reebok finds an imitator shoe, like the fake-Pump “Rumps,” the company sends Sterne Kessler half the pair. The lawyers snoop and shop for knock-offs as well.