Rich list entrepreneurs David Goldberger and David Wieland have launched an extraordinary public attack against ACCC chairman Graeme Samuel, calling for an inquiry into what their former business partner knew about the problems at shopping centre chain DFO.

Goldberger, Wieland and Samuel are all investors in Austexx, the company which owns eight DFO shopping centres along the eastern seaboard. The company struck trouble in August and almost collapsed under $1 billion of debt, until it was rescued by its banking syndicate.

Samuel, who owned his interest in Austexx through a blind trust, is believed to have lost tens of millions of dollars due to Austexx’s problems and was clearly shaken by the incident.

“This is most distressing indeed because it affects the interests of my children and grandchildren as beneficiaries of my estate,” he said at the time.

However, Goldberger and Wieland — who were valued earlier this year at $625 million on BRW’s Rich 200 — have questioned how much Samuel knew of DFO’s woes and how much information was passed to him by the trustees of his blind trust. According to a report in The Australian, Samuel’s son Warren Samuel is the secretary of the trust.

Goldberger and Wieland, speaking through their lawyer Leon Zwier of high-profiled Melbourne firm Arnold Block Leibler, told The Australian that they want a “full, open and transparent inquiry about DFO” and potential conflicts of interest with Samuel’s role as ACCC chair.

“If the ACCC does not maintain the highest standards of governance, the ACCC as a regulator cannot make either criticism, or demands, of boards to ensure executive officers remedy corporate culture and comply with the Australian anti-trust law,” Zwier said.

Samuel told Crikey sister website SmartCompany today that he would not be commenting on the matter. The ACCC also declined to comment. SmartCompany also attempted to contact Arnold Bloch Leibler and David Goldberger.

Samuel has been sensitive to the potential for conflicts between his investment in Austexx and his role as ACCC chairman. In August, Samuel stood aside from ACCC’s deliberations on the merger between NAB and AXA Asia Pacific, saying NAB was one of the bankers in the Austexx syndicate.

“Mr Samuel advised that he considered this course of action necessary to remove any perception of a conflict of interest arising from current issues concerning his family’s investment in the DFO shopping centre chain,” the ACCC said in a statement released at the time.

What is particularly surprising about the bitter falling out between Goldberger, Wieland and Samuel is the highly public nature of the rich list members’ attack. Goldberger and Wieland, who are best known as the founders of a series of petrol wholesaling and retailing businesses — including Liberty Oil — have traditionally kept a low profile outside of business circles, although they remain prominent members of Melbourne’s Jewish community.

While Goldberger and Wieland had invested with Samuel in various projects during the 1980s and 1990s, it is believed the relationship between the trio started to sour in 2004, when the ACCC made a number of decisions damaging to petrol companies, including Liberty Oil. It has also been reported that Samuel’s lawyers and trustees blocked potential deals to rescue Austexx until the very last minute, when a deal was negotiated between the legal teams representing Goldberger and Wieland and Samuel.

But while Goldberger and Wieland are strangers to public spats against high-profiled regulators, the pair’s lawyer, Leon Zwier, is not. He famously represented Richard Pratt during the ACCC’s long-running legal battle with the late paper and packaging mogul over allegations of cartel behaviour and misleading an ACCC inquiry.

In 2008, when the ACCC accused Pratt of lying, the battle became personal after Zwier repeatedly referred to “Graeme Samuel’s ACCC” in one famous media statement. “Mr Pratt expected that in resolving his disputes with Graeme Samuel’s ACCC, he would be given a fair go,” Zwier told reporters at the time.

Samuel is set to appear before a senate estimates hearing on October 21, as part of his regular duties as ACCC chair. His term as ACCC chair finishes next year, although he could be reappointed, as he was in 2008 by the Rudd Labor government.

*This article originally appeared on SmartCompany