The federal malpractice lawsuit alleges Kentucky-based accountant Michael Wertheim and Welenken CPAs enabled Charles Banks IV of Atlanta to defraud Garnett through businesses in which Garnett and Banks shared an interest.
The lawsuit contends Wertheim "possessed actual knowledge that Banks was helping himself to millions of dollars of Garnett's money and did nothing about it."
"Banks intentionally ... looted Garnett of his earnings and assets for many years, including the many years that Welenken and Wertheim provided accounting services to Garnett and his business interests," according to the lawsuit, which was initially filed in Hennepin County District Court and moved Wednesday to U.S. District Court in Minneapolis.
Defense attorney Greg Simpson told the Star Tribune his clients deny the allegations and will "vigorously" fight the suit.
Banks was not named as a defendant. Banks was sentenced last year to four years in federal prison for defrauding another former NBA star, retired San Antonio Spurs player Tim Duncan, of millions of dollars. In one of Duncan's deals with Banks, Duncan said he was told Garnett would be a partner.
Garnett's attorney, Mark Gaughan, declined to say why Banks was not named as a defendant. Gaughan said that "based upon the facts, we are confident this matter ultimately will be resolved in Mr. Garnett's favor."
The lawsuit claims Wertheim "took direction from Banks and for some reason chose to have virtually no contact with Garnett."
According to the lawsuit, Wertheim prepared financial statements, was a registered agent for companies in which Garnett held a financial interest, and added his name to bank accounts holding Garnett's money.
Wertheim also "worked in concert" with Banks to put Garnett on an allowance and set budgets that the 15-time NBA all-star was urged to follow, the suit read.
Garnett retired with the Timberwolves in 2016.