A senior executive of the Catholic Superannuation fund failed to declare that companies associated with his brother won marketing contracts worth $2 million with the fund, an inquiry has heard.
Catholic Super's general manager of institutional relations Robert Clancy also charged $46,000 in unauthorised expenses to his company credit card but repaid the sum, the banking royal commission heard.
The conflict of interest concerns centred on marketing and communications organisation Australian Family, which has provided services for the $9.3 billion industry super fund a number of times since 2010.
The commission heard Mr Clancy's wife Jennifer Kernahan was a shareholder in a company in the Australian Family network and his brother Paul Clancy was the Australian Family CEO.
Catholic Super has paid $2 million to Australian Family since 2013, which included money for a branding exercise and $500,000 for sponsorship expenses.
Catholic Super deputy chair Peter Haysey said the relationship with Mr Clancy's wife was disclosed in 2015.
The fact Paul Clancy was CEO of Australian Family and sole director of a consulting firm that formed part of the Australian Family network was only disclosed last month, the commission heard.
Mr Haysey said it was disclosed for the first time on July 18, when he insisted it be put on the conflict of interest register.
Mr Haysey said there was a control put in place that only Catholic Super CEO Frank Pegan would have a relationship with Australian Family but he was not satisfied that was the case.
"There are numerous examples of email correspondence between the brothers which are a breach of not only the conflict policy but the email and internet policy, for example," he told the commission on Wednesday.
Mr Haysey said Mr Clancy had been placed on leave and the matters were being investigated.
The amount paid to Australian Super was being independently reviewed.
Mr Haysey said Catholic Super discovered in 2016 Mr Clancy had charged $46,000 in unauthorised expenses, which had since been repaid.
Mr Haysey said he and the board did not know about the issue until he found a letter written by someone in the fund's legal team in Mr Clancy's drawer after he was placed on leave "a matter of weeks ago".
The commission heard Catholic Super's long-standing practice allowed senior executive staff to charge personal travel and accommodation to their corporate credit card, provided it was immediately repaid.
Mr Haysey said that practice had now stopped.