Page Six reported back in December that superagent Ari Emanuel was shopping a memoir that he’s writing with JR Moehringer — the ghost writer behind tomes by Prince Harry and Will Smith, among others.

Now we’re told the he’s sold it to Knopf.

Sources tell us there’s a lot of confidentiality surrounding the book at the publishing house.

Emanuel’s clients have included Mark Wahlberg, Larry David, Martin Scorsese, Conan O’Brien and Charlize Theron.

“Think of it as Ari’s ‘Shoe Dog’ or ‘Spare,’ ” an insider told Page Six — referring to the 2016 memoir by Nike co-founder Phil Knight and Harry’s 2023 memoir — when we first broke the news.

Emanuel founded Endeavor, which merged with WME in 2009 and also headed TKO Group Holdings, owner of the UFC and WWE.

The deal lands as one of his famous siblings, Dr. Ezekiel Emanuel, dropped a best seller, “Eat Your Ice Cream: Six Simple Rules for a Long and Healthy Life.”

His other brother is Rahm Emanuel, former mayor of Chicago.

Reps did not immediately comment. The book was being repped by WME, natch.

Pulitzer Prize winner Moehringer doesn’t do books for less than $1 million, we’ve previously reported.

The star writer was also behind Andre Agassi’s book, “Open: An Autobiography,” a runaway bestseller.

His own memoir, “The Tender Bar,” was turned into a 2021 film starring Ben Affleck and directed by George Clooney.