A federal judge in Minneapolis has thrown out a lawsuit against Associated Bank alleging that the Green Bay, Wis.-based financial institution had knowingly aided a $194 million Ponzi scheme that defrauded nearly 700 investors nationwide in the aftermath of the Great Recession.

The lawsuit was filed in April 2013 by a Minneapolis attorney whose firm was appointed by former Chief U.S. District Judge Michael Davis to round up assets for investors who had been bilked by Trevor Cook and his associates in what they had pitched as a surefire investment in foreign currencies. They attorney, R.J. Zayed, was a former federal prosecutor who had gone to work for the Minneapolis law firm Carlson, Caspers, Vandenburgh, Lindquist and Schuman.

Cook and his associates were convicted and are serving lengthy terms in federal prison.

Neither the bank nor any of its employees were charged in the scheme.

In a 22-page order issued Tuesday, U.S. District Judge David S. Doty dismissed the receiver’s lawsuit against Associated Bank. He said that to find the bank liable, there must be evidence that it had “actual knowledge” of the fraud, and he found that “no reasonable jury” could reach such a conclusion.

The receiver filed a notice of appeal to the 8th Circuit in St. Louis.

The receiver’s allegations center on Lien Sarles, a former vice president of Associated Bank who oversaw the accounts for Cook, his colleague Patrick Kiley, and various business entities involved in the scheme. Sarles had helped open a bank account in the name of Crown Forex LLC, which was integral to the Ponzi scheme. Sarles opened the account though the business never provided the required state registration documents.

Doty found that while Sarles had socialized with Cook and Kiley, the evidence demonstrates nothing more than a normal client relationship. And although Sarles had violated the bank’s policies by overriding identification-check procedures when opening some accounts for Cook and his business entities, he noted that it’s undisputed that such overrides were common at Associated Bank.

“At most, these facts indicated negligence on the part of the Bank in maintaining adequate policies and procedures,” Doty wrote. He noted that the U.S. Comptroller of the Currency had already hit the bank with a $500,000 penalty for its “inadequate Bank Secrecy Act and Anti-Money Laundering program.”

Christopher Pettengill, who pleaded guilty in the scheme, testified that Sarles had attended meetings with Cook, Kiley and other associates. But Doty found that at most, his testimony supports “a weak inference that Sarles should have inquired further into the Crown Forex account. But to further infer, based upon that weak inference, that Sarles had actual knowledge is a step too far,” he wrote.

Similarly, Doty found that the evidence supports — at most — a conclusion that bank officials may have been negligent in maintaining adequate account policies, but that’s not insufficient to hold it accountable for aiding and abetting the scheme, as the receiver alleged.

“Even if there were some evidence of actual knowledge, there is no evidence that the Bank substantially assisted the fraud,” Doty wrote. He granted the bank’s motion for summary judgment.