Customers defrauded by a company that falsely promised to patent and market their ideas in exchange for thousands of dollars say they're shocked to see one of its board members serving as U.S. attorney general.

A federal court shut down Miami-based World Patent Marketing as part of a $25 million settlement following an investigation by the Federal Trade Commission, which subpoenaed Matthew Whitaker as part of the probe, reported the Washington Post.

It's not clear how Whitaker responded to that 2017 subpoena, which comes under new scrutiny after President Donald Trump tapped him Wednesday to replace Attorney General Jeff Sessions.

Whitaker, a former U.S. Attorney, joined the company's advisory board in 2014, after a failed run for U.S. Senate in his home state of Iowa.

WPC's founder, Miami businessman Scott J. Cooper, had donated $2,600 to that Republican campaign, and he highlighted Whitaker's career in law enforcement to establish credibility for the company.

Whitaker promoted the company's clients in online videos and wrote a threatening email to one client that cited his background as a U.S. Attorney, but a court receiver said there's no evidence he knew company salespeople were making false promises to inventors.

One of the duped customer, Ryan Masti, lost $77,000 after WPC promised to help him market his idea for a social media app to help disabled people.

“It’s really upsetting to know that guy will be attorney general,” said the 26-year-old Masti. “It’s so offensive. It’s like a stab in the back.”

Whitaker, who was paid at least $10,000 by WPC, did not respond to requests for comment, and so did a Justice Department spokeswoman and a partner at his former Iowa law firm.

The company did not admit or deny wrongdoing as part of the fraud settlement.

Mati, who voted for Trump, said he was struggling under crushing debt after losing his money in the scam, and he said company representatives told him that Whitaker had personally reviewed his idea and believed it would succeed.

“They said he’s very high up, he’s a professional -- he’s got a lot of power,” Masti said. “That’s how they sold you.”

Another former customer, Penn Mason, said he paid $21,000 for help patenting and marketing a real estate app he created -- but got nothing in return.

“That was our money,” said the 52-year-old Mason.

He can't believe one of the advisory board members is acting as the top law enforcement official in the country.

“It makes me sick to my stomach," Mason said. "It’s like a punch in the gut.”