Damaging evidence presented to the Hayne royal commission might already be burning a hole in customer support for bank-owned super funds, which collectively suffered market share losses in the year to June.The latest superannuation flow data published by APRA show that industry funds grew assets under management at double the system growth rate of 8 per cent in the last financial year.Industry funds such as Australian Super collectively grew by 16 per cent compared to an average of 6 per cent for retail funds such as NAB's MLC subsidiary and CBA's Colonial arm.The data also indicate that the industry fund sector has edged ahead of retail fund providers in terms of the total retirement savings assets they manage.The industry and retail super sectors each now manage slightly more than A$600 billion on behalf of super members.That equates to almost identical market shares of around 23 per cent each of the $2.7 trillion superannuation pie in Australia.Self-managed super funds remain the largest sector with almost $800 billion of assets under management.Goldman Sachs analyst Ingrid Groer observed in a report to clients that the latest data partly reflected a growing preference for industry funds among retirement savers.Retail funds also suffered net outflows in the June quarter, she noted.Groer said the older customer base of retail providers was starting to erode funds under management."The retail fund sector has an older customer base and thus benefit payments are now offsetting a large portion of contributions," she told clients.NAB and CBA are actively seeking buyers for their wealth management arms, while ANZ is in the process of transferring its financial advice business to IOOF.Evidence heard by the royal commission indicates that NAB might face criminal charges for levying fees on customers when advice services were never provided.