Goldman Sachs turns tables on tell-all author

Goldman Sachs will tell you why Greg Smith quit: money.

The Wall Street firm — caught off guard by Smith’s broadside against the bank eight months ago — moved to combat Smith’s forthcoming tell-all, “Why I Left Goldman Sachs,” before it hits Monday.

Goldman yesterday fired off a nine-page summary of its investigation into allegations Smith made in a New York Times Op-Ed in March, in which he blasted the bank’s culture as morally bankrupt. As evidence, Smith said that bankers routinely referred to clients as “muppets” — British slang for idiots.

Goldman’s investigation portrays Smith as a perennial underachiever with an exaggerated sense of self-worth who was fed up because he wasn’t making as much as his peers after 12 years with the bank.

According to a copy of the report obtained by The Post, Smith complained to one of his managers in 2011 that he deserved $1 million in compensation for his work the prior year rather than the $700,000 in pay, including a $500,000 bonus, he had received.

“Greg Smith off the charts unrealistic, thinks he shld [sic] trade at multiples,” one of his managers wrote in a January e-mail. “We told him there’s little tolerance for reactions like that and he needs to tone it down.”

Goldman’s investigation found nothing to support allegations that the firm’s culture was toxic and disrespectful toward clients. The probe turned up one e-mail reference to “muppets” but determined that it was an attempt to explain a complicated trade rather than demean the client.

Smith’s memoir is being published by Grand Central Publishing, a division of France-based Hachette Book Group, which reportedly paid him a $1.5 million advance.

The book bears the same title as his poison-pen resignation letter, which caused a stir both inside and outside the investment bank. Goldman, struggling to restore its reputation after a wave of negative publicity, was blindsided by the attack.

The bank is trying to get ahead of media coverage tied to the book’s publication, including Smith’s sit-down with “60 Minutes” on Sunday.

Goldman declined to make execs available to the program because the publisher wouldn’t provide an advance copy of the book unless executives signed a non-disclosure agreement.

A copy of the 288-page book obtained by The Post reads like a Wall Street coming-of-age tale, featuring cameos by Goldman CEO Lloyd Blankfein and President Gary Cohn.

But outside of a brief dip in a hot tub at the Mandalay Bay in Las Vegas with “Ms. Silicone,” a woman known for her surgically augmented breasts, and former Goldman partner David Heller, there’s little sizzle.

Sources say that Goldman did receive a copy of the book on Wednesday and reviewed it. Goldman was expected to largely ignore the book but ended up taking a pre-emptive stance by releasing the results of its investigation.