Fight on board airliner boosts 'Knee Defender'

Knee-Jerk Reaction

Is there such a thing as a "right to recline?" Social media debated it this week after two passengers were kicked off a United Airlines flight for arguing over a reclining seat—or rather, a nonreclining seat.

A female traveler allegedly threw water in a male passenger's face for refusing to remove a device called the "Knee Defender," which prevented her from moving her seat back.

The 6-foot-3-inch inventor of the device, Ira Goldman, said legroom wars have been a problem for a long time, but said he didn't imagine an argument going this far. "The product's been on the market for 11 years, and this is the first time it's happened," he said.

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The Knee Defender is a device Goldman created in 2003 and sells on his website for $21.95.

Goldman, who's based in Washington, has been riding high off the publicity, with more than 185,000 people visiting his website the day after the incident. His site typically attracts roughly 500 users a day. He wouldn't reveal specific sales figures, but isn't shocked that people are eager to buy his gadget.

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"It's a courtesy issue," he said, adding that blame lies with the airlines, not his device. "If someone's sitting behind you and the person's legs are already there, then the airline is trying to do what they did in 'The Producers.' They sell me the space for my seat, for my legs and then they sell the space to somebody else to recline. But obviously the reclined seat and my legs can't be there at the same time."

Goldman actually includes a courtesy card with the device that tells customers to be conscientious of other passengers and to listen to the flight crew, which didn't happen on the United Airlines flight.

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Some airlines prohibit the use of the Knee Defender, but it's not illegal.

"The FAA only gets involved when it's a safety issue," Goldman said. "And this is not a safety issue."

—By CNBC's Marqui Mapp