Institutional investors held around half of total equity exchang-traded fund assets in 2012, according to a new report from Strategic Insight.

Institutional presence was heaviest among international equity ETFs, beating out ownership by individual investors and financial advisers with holdings of 57% of total assets. Two main reasons for the presence in international equity ETFs: the opportunity to invest in emerging markets and quick exposure to liquidity in emerging wealth regions, said Dennis Bowden, assistant director of U.S. research at Strategic Insight.

Within U.S. equity ETFs, the institutional market segment accounted for about 46% of ETF assets, but a larger share of aggregate activity in 2012. Institutional investors injected $33 billion into U.S. equity ETF strategies over the year, which exceeded demand for core U.S. equity ETFs within the retail space, estimated at $10 billion.

"At times, individual investors' use of ETFs is assumed to mirror overall industry ETF trends. Our research suggests, however, that institutional investors are using ETFs differently than individuals," Bowden said. "Therefore assuming that aggregate ETF trends are always reflective of how individuals use ETFs can at times be misleading."

Retail investors still dominated the bond ETF space, holding 70% of total bond ETF assets as of the end of 2012.

Overall, the retail marketplace still holds the majority of ETF assets. Retail investors held 58% of assets at the end of 2012, compared with 42% for institutional investors.

The private bank channel led the charge for ETF asset holdings, with roughly $276 billion at the end of 2012. The channel gained $46 billion in 2012 flows.

The RIA channel followed with $267 billion in aggregate ETF holdings and around $28 billion in 2012 inflows.