National Australia Bank Ltd. fought off rivals to renew its custody contact with MTAA Super Fund, a business relationship that will now last more than 15 years.

The bank, which has a 30 per cent market share of Australia’s custody business, has yet to finalise the length of its contract with MTAA Super, which manages about $6 billion. MTAA Super was advised by consultants Thomas Murray.

“Key factors in our decision to re-appoint NAB were its focus on and expertise in asset servicing for superannuation fund assets, and in particular its expertise with our mix of assets,” says MTAA Super’s chief executive Leeanne Turner in a statement.

The bank’s successful defence of its custody contract with MTAA Super dampens speculation and the sniping its rivals have made regarding the sustainability of its predominance in the local market.

National Australia Ban’s asset servicing unit had $556 billion in assets under custoday as of June 30, 2011 from a total investment pool in Australia of $1.86 trillion, according to the Australian Custodial Services Association.

“We’re looking forward to another strong year ahead for 2012,” says Brian Keogh, general manager sales, relationships and financial market services, asset servicing at National Australia Bank, in a statement.

QSuper, the $30 billion fund, is expected to decide who will win its custody contract this month. National Australia Bank is the incumbent custodian.

Custodians charge between 3 basis points to 7 basis points based on a client’s assets under management. The bigger a fund’s assets under management are, the lower the fees a fund is charged by a custodian.