The estate of artist Joan Mitchell has demanded Louis Vuitton pull a new advertising campaign, which allegedly features at least three art works by the late abstract painter that were used without permission.

On Tuesday, the Joan Mitchell Foundation (JMF) said it sent the French house a cease and desist letter requesting the immediate withdrawal of the campaign, which stars French actress Léa Seydoux.

According to the foundation, the LVMH-owned brand repeatedly requested permission to use the images by Mitchell in an advertising campaign late last year. The requests were denied in writing, the foundation said, citing its longstanding policy of only using the artist’s works for educational purposes.

The three artworks in question are currently on display at the Fondation Louis Vuitton, the Parisian art museum belonging to the brand’s parent LVMH. By allowing the paintings to be featured in the campaign, the museum is in violation of its agreement with the Joan Mitchell Foundation, it said.

”It is a grave disappointment to JMF that Louis Vuitton has such disregard for the rights of an artist and would exploit her work for financial gain,” JMF said in a statement. “If Louis Vuitton does not promptly halt this campaign and cease the illegal use of Mitchell’s artworks, JMF will promptly take further legal action to address this matter.”

Louis Vuitton did not immediately respond to a request for comment.

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