It is pretty complex but the ability to continue to use tax losses is contingent on Calliden being able to meet the ATO's "same business" and "continuity of ownership" tests.
Calliden CEO Nick Kirk did his best to explain the situation in a press release of 1 July 2013, on pages 3 and 4. I hope the following link takes you there. If not you can access it thru the Calliden investors web page. As I read it, it is not beneficial to our case if all those shares have gone to the one purchaser, but as I said, it is complex and I hope the company can provide a more authoritive view in the not too distant future.
As far as I can see from the most recent shareholder details (in recently issued 2013 Ann Rpt), Hunter Hall (10.8%) and Australian Unity are the only shareholders to hold more than 10% holdings. Hunter Hall were originally 20%+ but have been selling down over recent time. Challenger (9.2%), Greencape (8.2%) and Naos (6.8%) are other shareholders over 5%.
With Australian Unity being a business partner of CIX, hence the comment about Hunter Hall.