Sen. Edward M. Kennedy, the most prominent surviving member of the Kennedy family, has agreed to sell his memoirs for an advance of more than $8 million, people with knowledge of the negotiations say.

After a six-day auction that concluded Nov. 19, Twelve, an imprint of Grand Central Publishing, bought world rights for the autobiography. Before the deal can be completed, Kennedy must clear his publishing contract with the Senate Ethics Committee.

Jonathan Karp, publisher and editor in chief of Twelve, said he hoped to publish the book in the fall of 2010.