Passengers sued United over its windowless window seats. Now the airline wants the suit thrown out.

When is a window not a window?

United Airlines is trying to get a lawsuit dismissed by arguing that a window seat only means one next to a wall, and not necessarily with a view.

In August, United and Delta Air Lines were sued by passengers in two separate but similar suits. Both airlines were accused of unfairly charging extra for some window seats without warning that there wasn't actually a window there.

United filed a motion to dismiss the case on Monday.

"The use of the word 'window' in reference to a particular seat cannot reasonably be interpreted as a promise that the seat will have an exterior window view," the airline's lawyers wrote.

"Rather, the word 'window' identifies the position of the seat—i.e., next to the wall of the main body of the aircraft," they added.

The lawyers also pointed to United's contract of carriage, which does not expressly promise that window seats have exterior views.

Aviva Copaken, a plaintiff in the United suit, said she paid as much as $169.99 to choose a window seat, only to find out upon boarding that she only had a view of the cabin wall.

Boeing 737 planes, which make up over half of United's fleet, have at least one row with a missing window due to the placement of ducts, electrical conduits, or other components. Airbus A320s and Boeing 757s can also have missing windows.

While American Airlines, Alaska Airlines, and Ryanair are among the airlines that warn customers about this in the booking process, United and Delta do not, the suits say.

Carter Greenbaum, representing plaintiffs against United and Delta, told Reuters that United's position was "contrary to the reasonable expectations of countless passengers who unknowingly paid extra money for windowless window seats."

"Consumers deserve better than empty promises and United's word games," he added.

United did not immediately respond to a request for comment sent outside US working hours.

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