1. "UNG's complex underlying strategy has been made riskier by regulatory uncertainty." Read more here.

2. "Since DTO is both leveraged and futures-based, this fund faces double the regulatory uncertainty in the months ahead." Read more here.

3. (with FAZ) "While sophisticated traders may find these funds effective daily hedges for more complex strategies, they can be devastating to buy-and-hold investors who don't understand their objectives." Read more here.

3. (with FAS) "While sophisticated traders may find these funds effective daily hedges for more complex strategies, they can be devastating to buy-and-hold investors who don't understand their objectives." Read more here.

4. "When the trends that propel funds like DBV reverse, they can quickly erase gains that have taken months to accumulate." Read more here.

5. (with DMM) "Since UMM and DMM are tied financially, a creation in one of these funds will spark a creation in the other. Investors can get burned when fund managers take money from one pocket and put it in the other." Read more here.

5. (with UMM) "Since UMM and DMM are tied financially, a creation in one of these funds will spark a creation in the other. Investors can get burned when fund managers take money from one pocket and put it in the other." Read more here.

6. (with VXX) "These ETFs track market volatility through the use of derivatives, and their complex strategies make them appropriate for only the most sophisticated investors." Read more here.