Another area within actively managed ETFs that is taking shape is the  non-transparent actively managed fund. This would require the fund to disclose holdings once per day, at the end of the trading session, similar to a mutual fund. BlackRock recently made this request in a filing. [BlackRock Files to Launch Active ETFs]

This request dodges one of the main hold-ups in the proliferation of active management with ETFs. The requirement of full portfolio disclosure with actively managed ETFs could lead to “front running.” Many providers and managers are gun-shy to launch an actively managed ETF until this issue can be resolved.

Some of the most successful active ETFs trading are Pimco Enhanced Short Maturity Strategy Fund (NYSEArca: MINT) with $1.44 billion in assets under management, and the WisdomTree Dreyfus Emerging Currency Fund (NYSEArca: CEW) with $574 million in assets.

Tisha Guerrero contributed to this article.