These ETFs Save Investors a Trip to the Casino

Exchange-traded funds are looking for a few good gamblers.

ETFs are famous for tracking simple, broadly diversified indexes cheaply, transparently and tax-efficiently, an ideal combination for long-term investors. The problem for aspiring issuers is that the market for those ETFs is dominated by the big three — BlackRock Inc., Vanguard Group and State Street Corp. — which collectively manage 82 percent of ETF assets, according to Bloomberg Intelligence. To stand out, smaller firms are turning to more complex and niche funds.