Beginning in 2008, art buyer Joao Tovar paid $481,625 for 10 sculptures of the word PREM, a Sanskrit term meaning "love," from a one-time business partner of renowned pop artist Robert Indiana, Tovar said in the lawsuit filed in superior court in Rockland, Maine.

Tovar says he bought the sculptures from longtime Indiana associate John Gilbert because he believed Indiana had officially licensed their production.

Indiana, who lives on an island off the Maine coast, renounced the sculptures in a 2009 letter to New York dealer Simon Salama-Caro, saying they had been conceived by Gilbert in India and made without his permission. The move led auction house Christie's to remove them from an upcoming sale.

Best known for his 1964 block letter creation featuring an L-O arranged on top of a V-E, Indiana's works are part of the permanent collection of major museums including the Museum of Modern Art, the Smithsonian Institution and the Whitney Museum of Modern Art. The LOVE design, on which the PREM sculptures were based, was featured on an 8-cent U.S. postage stamp issued on Valentine's Day in 1973.

Indiana's denial of his approval "rendered the sculptures worth little more than the materials from which they were made," says the suit, which was filed April 30. Further complicating the matter, Tovar's suit says some of the works he bought have been sold multiple times, most recently for a total of $1.1 million.

Indiana, reached by telephone this week, told Reuters he "absolutely" denied the allegations in the suit but declined further comment.

Tovar says that he relied upon a 2008 certificate of authenticity provided by Gilbert that includes Indiana's signature and the words "To Tovar" at the bottom of the page near Gilbert's signature. Court filings show that Indiana acknowledged that the signature on the document was his but that it was meant as a souvenir for Tovar, rather than acknowledgement that the work was his.

On April 24, Gilbert and Indiana settled a dispute in federal court in New York over the PREM works after a judge found that Gilbert had attempted to "force an artist — here, defendant Robert Indiana — to acknowledge creation of a work that the artist did not create and does not like; and then plaintiff could and would use such acknowledgement in selling such works to the public as authentic creations by the artist."

The judge in that case also found that Indiana had made an agreement with Gilbert in 2007 under which Indiana would use Sanskrit characters to design a PREM sculpture that Gilbert could produce and sell. That agreement did not cover the design of a PREM sculpture using the Latin alphabet - like the work purchased by Tovar - because Indiana felt such a design "looked like a refrigerator," according to court documents.

(Editing by Barbara Goldberg and Vicki Allen)

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