High-rolling investors have positioned themselves bullish on Opendoor Technologies (NASDAQ:OPEN), 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 OPEN often signals that someone has privileged information.Today, Benzinga's options scanner spotted 19 options trades for Opendoor Technologies. This is not a typical pattern. ...