The billionaire founder of a Boston-based equity firm joins Patriots owner Robert Kraft as one of the ultra-rich caught up in the months-long police probe of Florida massage parlors, authorities said.

John Childs, 77 — of J.W. Childs Associates — is wanted on a solicitation of prostitution charge, according to a warrant for his arrest obtained by TCPalm.com. He has not been arrested.

Childs firmly denied any involvement in the ring.

“The accusation of solicitation of prostitution is totally false. I have retained a lawyer,” he told Bloomberg News. “I have received no contact by the police department about this charge,” he said.

Childs, who lives seasonally in Indian River Shores and lives part-time in Boston, has donated to several Republican politicians and groups — including former US House Speaker Paul Ryan, 2012 presidential candidate Mitt Romney and Club for Growth, TCPalm.com reported.

He’s contributed about $4.3 million to Republican candidates — as well as political action committees — last cycle, campaign finance records obtained by the outlet show.

Since it was founded in 1995, his firm has invested roughly $3.7 billion of equity capital into 50 businesses, its web site says.

On Friday, Kraft — also 77 years old and a billionaire — was named as a suspected john in the sweeping investigation.

He was caught on camera engaging in sex acts in a seedy parlor— the Orchids of Asia Day Spa — shortly before his team won its sixth Super Bowl, cops said.

He faces two counts of soliciting another to commit prostitution, Jupiter Police Chief Daniel Kerr said during a press conference.

A spokesman for Kraft and the Patriots said Friday, “We categorically deny that Mr. Kraft engaged in any illegal activity. Because it is a judicial matter, we will not be commenting further.”

Finance titan John Havens, Citigroup Inc.’s former president and chief operating officer, was also charged in connection with the sting, cops said.

“We are working in conjunction with numerous jurisdictions and local agencies to try to arrest all subjects we have active charges on,” Vero Beach Police Public information Officer Bradley Kmetz told Bloomberg. “We encourage people who have active arrest warrants to turn themselves in,” he said.