Twenty years ago the figure skating world was rocked by an attack on one of its most prominent stars, Nancy Kerrigan.

The incident happened at the U.S. national championships, which serve as the Olympic trials, and there was only one camera crew whose cameras were rolling in Detroit's Cobo Arena when Kerrigan was clubbed in the leg by Shane Stant.

The footage belonged to the Chicago-based sports and entertainment company Intersport, which happened to have cameras trailing Kerrigan as part of a special it was filming.

Charlie Besser, who founded Intersport in 1985, immediately told producers to embed an "Intersport" logo into the footage. He then shopped the clip to national news outlets, eventually settling on ABC News because that's who had originally contracted Intersport to film Kerrigan, the eventual Olympic silver medalist that year in Norway.

An excellent feature in Crain's Chicago Business reveals just how much Intersport has profited on the clip in the two decades since the attack. Whenever anyone wants to use the footage they've got to acquire the licensing rights from Intersport. That includes documentaries, news features and any other type of story.

Fees are typically around $10,000 or $15,000 per use (roughly $250 per second), and Besser told Crain's that he has gotten more than a dozen requests in the lead-up to the Sochi Olympics.

"When Tonya Harding gets married, we get calls. When Nancy Kerrigan gets married, we get calls. When somebody has a baby or gets divorced in that group, we get calls," Besser said. "It's kind of crazy, but it just keeps going."

Intersport uploaded the below footage of the attack to YouTube last month.

The revenue from the Kerrigan attack footage has netted Intersport a seven-figure sum, but that's a fraction of the company's total revenue. The company makes $100 million a year from various sponsorships, and three years ago the NCAA paid it $17 million for the rights to use the phrase "March Madness," which Besser had trademarked.