trading activity of recent top 30 entrants, page-5

And if you suspect a nominee account of being an unidentified instutional shareholder simply ring CDU and ask them who the beneficial owner of the nominee account is.

Unless its changed recently Section 672A of Corps Act (2001) gives companies the right to obtain disclosure of the beneficial owners of the shares.

If you think there is a conspiracy the company should be able to set you straight pretty quickly.