Attorney General Maura Healey's office asked the state's appeals court on Friday to block the sale that's set to begin Monday so she can appeal a lower court ruling that cleared the way for the artwork to be auctioned off.
A judge on Tuesday denied the bid to stop the sale by the Berkshire Museum in Pittsfield.
Rockwell's three sons are among those fighting the sale. His family said in a statement released through attorneys Friday that his artwork should remain in the Berkshires "as he intended" and "for all to enjoy."
The museum has stood by its decision to sell the artworks.
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