NEW YORK (AP).- A copy of the Emancipation Proclamation signed by President Abraham Lincoln that was purchased by Robert F. Kennedy sold Friday for more than $3.7 million, an auction record for a U.S. presidential document. Kennedy bought the printed copy of the 1863 document declaring all slaves “forever free” shortly after its centennial celebration at the White House. It was sold for $3,778,500 to an anonymous bidder at Sotheby’s by Kennedy’s widow, Ethel. The price included a buyer’s premium. The maximum presale estimate was $1.5 million. It’s one of 48 printed copies signed by Lincoln. About half are known to survive; 14 are in public institutions, and eight to 10 are privately owned, Sotheby’s said. The original handwritten Emancipation Proclamation is in the National Archives. The previous record was achieved at Christie’s New York in February 2009 for Lincoln’s 1864 victory speech after he was re-elected as president.