An elderly woman sued the Gagosian Gallery, claiming it allowed her son to sell a major work by pop artist Roy Lichtenstein, without her permission, for far less than its true value.

Ninety-three-year-old Jan Cowles sued Larry Gagosian and the Gagosian Gallery, in New York County Court.

She claims that her son Charles Cowles, an art dealer in New York City, sold her Lichtenstein enamel, "Girl in Mirror," out of financial desperation, while his mother suffered "moderate to severe dementia."

Charles Cowles is not a party to the case.

The complaint states: "By 2008, Charles Cowles suffered large financial losses and was in desperate financial condition. Charles's financial distress was known to Gagosian; and, in fact, the closing of Charles's gallery was reported in a large article in the 'New York Times' in June 2009, which refers to Charles Cowles Gallery as the 'most recent casualty' in the contemporary art market, and quotes Charles as commenting that '[i]t's shocking how bad business has been.'

"Unknown to Mrs. Cowles, by 2008 Charles had sold some of her art collection without her knowledge or consent and failed to remit the sale proceeds to her."

Jan Cowles says that her attorney-in-fact Lester Marks discovered what her son was doing in December 2009, and immediately hired counsel to investigate it.

"The investigation revealed two transactions between Charles and Gagosian regarding two major works of art: one involving a painting by Mark Tansey, and the other concerning the Lichtenstein work."

The Tansey work, "The Innocent Eye Test," was the subject of a similar lawsuit that Jan Cowles filed in May 2011.

Her new lawsuit, filed Wednesday, details the alleged fraud involving the $5 million Lichtenstein work at greater length.

"In or about October 2008, Gagosian somehow learned that Mrs. Cowles owned the Lichtenstein work," the complaint states. "Rather than contacting Mrs. Cowles directly, however, Gagosian chose to contact Charles Cowles to inquire as to whether Mrs. Cowles would consider selling it. Thereafter, Charles took Larry Gagosian to Mrs. Cowles's apartment at a time when she was not present to view the work. Upon closely inspecting the work (which hung prominently in the apartment) and without expressing any undue concern about its condition, Larry Gagosian represented that he could achieve a sale price of $3 million or more. In fact, Gagosian was aware, another 'Girl in Mirror' in the edition of eight had been sold almost a year and a half earlier, in May 2007, at an auction in Sotheby's for $4,072,000."