Media Super chair Gerard Noonan said industry funds' high levels of disclosure had left them open to claims of misuse of member money and under-the-table payments.
Media Super has boosted disclosure in its 2011-12 annual report, including the salaries of its top-paid executives and payments to industry organisations to release directors from their day-to-day duties.
"It's one of the difficulties in disclosing this information - we leave ourselves a little bit open to what I think is a completely spurious charge that money is being paid to employer associations or unions as though it shouldn't be paid there.
"It's the downside of good disclosure," he said.
Noonan said finding information on retail funds was near impossible, including the names of the trustees. He said it was because many of the trustees were directors or senior executives of a bank.
"There's a clear conflict of interest between owning a for-profit and being the director of a trust where you are perhaps being obliged, or where there's a constitution about, whether you direct the investments back into the bank again," he said.
Noonan said that while industry funds had taken heed of the Australian Securities and Investment Commission's and the Australian Institute of Superannuation Trustees' improved disclosure requirements, other areas of the super sector should be looking more closely at access to information.