High-rolling investors have positioned themselves bearish on Alcoa (NYSE:AA), and it's important for retail traders to take note.\This activity came to our attention today through Benzinga's tracking of publicly available options data. The identities of these investors are uncertain, but such a significant move in AA often signals that someone has privileged information.Today, Benzinga's options scanner spotted 19 options trades for Alcoa. This is not a typical pattern.The sentiment among these major trader ...