This paper investigates the factors determining the order aggressiveness of institutional and individual investors on the Australian Stock Exchange (ASX). The study also examines the changes in institutional and individual investors’ order aggressiveness following the removal of broker IDs on the 28th of November 2005. While investigating the order submission strategies of stocks sampled from large, medium and small capitalization groups, we document that the institutional and individual investors’ order aggressiveness responds similarly to the market depth and the bid-ask spread, but differently to the time left-to-trade (end of the day) and the order size. This difference in the order submission strategies employed by institutional and retail investors is more strongly pronounced in the post-transparent (anonymous) market. In addition, both groups of investors become less aggressive
after the move to anonymity, with stronger results observed for individual investors