Don't take what I say here as gospel, but my understanding...

Don't take what I say here as gospel, but my understanding is:

1. Yes, buying via the US codes generates a contract note and investors who buy are regular shareholders in the company;
2. The technical definition of these dual listings is "ADR" or American Deposit Receipts which I believe allows one to buy stock in Australia and selling that stock in the US and vice versa all though I am not sure of the mechanics as to how one actually does that;
3. you might find the ADR's are a ratio or sort, I know when I had more professional tools I had seen conversion back to an AUD price.

This differs to listings in the UK where stock from Australia isn't transferrable and vice versa, frequently the difference between BHP's price in Australia compared to the fair equivalent price in the UK is frequently out of line, sometimes by a magnitude of +/-20% and is a phenomenon that attracts academic research.