Pages 3 and 4 are interesting in this link: http://www.asx.com.au/supervision/rules_guidance/asxl/asx_gn22_automated_order_p rocessing_operational_requirements.pdf
This link gives a list of ASX trading rules: http://www.asx.com.au/supervision/rules_guidance/market_rules.htm
This link is interesting in that it outlines the rules of Section 13:4 - "Prevention of Manipulative Trading". The ASX has these provisions in place, but relies on the rules being self-enforcing - there is very little anyone could do to prove manipulation - even course of sales data could be disputed.