The HarperCollins spokeswoman declined to comment on financial terms of the deal or elaborate on plans for the book, saying further details would be released in a statement on Friday.

Representatives for Knox, a 24-year-old former University of Washington student convicted of murder while studying in Perugia, Italy, said she would have no comment.

A source familiar with the deal said Knox would tell her story in the memoir, including details of the sensational case and her imprisonment in Italy.

The book deal follows a bidding war between U.S. publishers over rights to any memoir written by Knox with a price tag expected to be well over a million dollars, according to book industry insiders.

The memoir was considered a hot property because the world has yet to hear all the details from Knox, who was found guilty in 2009 of murdering her 21-year-old British housemate, Meredith Kercher, and spent four years in prison.

An Italian court in overturned Knox's conviction in October.

Also cleared was her boyfriend, Rafaele Sollecito, leaving Ivorian drifter Rudy Guede as the only person convicted in a killing investigators believe was carried out by more than one person.

The New York Times has reported that Sollecito has retained a literary agent to shop a book of his own.

Knox was also convicted of slander over statements she made under police questioning that falsely implicated bar owner Patrick Lumumba in Kercher's murder.

Earlier this month her Italian attorneys asked an appeals court there to overturn that conviction as well.

Kercher's half-naked body was found with stab wounds and a deep gash in her throat in the apartment she shared with Knox in Perugia, Italy in November of 2007.

Knox, a former University of Washington student, was released from custody following the ruling and returned home to Seattle, where she has largely avoided the public eye.

(Additional reporting by Dan Whitcomb; Editing by Bob Tourtellotte)

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