ETC (Electronic Transaction Clearing) is the ultimate custodian (DriveWealth is sub-custodian), where shares are held on a books and records basis. This is different to some other exchanges (ie : Australia which operates on a CHESS/HIN structure)

These are listed equities only, execution is via the US exchanges, routed through NBBO (National Best Bid and Offer) when required. 1 full share gives you a voting right, while a fractional component only gives you full economic interest as per the books and records at the custodian.