Ann: Becoming a substantial holder, page-16

To answer my own question the shortman site says that its data is sourced from ASIC, ASX and other third party data providers and that all data is reliant on accurate report submissions by individual sellers, of whose accuracy there can be no guarantee. This leads to other questions. Why would a short seller want to record that a sale is short? What is to be gained by so doing? If there is no incentive to report accurately why should we place any credence on the numbers? Somebody out there must know a lot more about this. Is there any chance of sharing the information?