The small trades are bots which manipulate the price in one...

The small trades are bots which manipulate the price in one direction or another by ticking it in just one or two units at a time. They do this all day long to keep the price at, or move it towards, their desired price (either up, down or the same depending on the owner's position being long or short).

The Ukw trades look like either centrepoint or cross-trades. Centrepoint is an asx settlement system that allows brokers to execute trades at a 4th decimal place to help with liquidity, and the cross trades are a manual transaction that brokers enter for trades between two of their clients. For example if a buy goes through Commsec from another seller who is also Commsec, Commsec can settle this themselves to 4 decimals and report it to the market instead of executing the trade on the ASX itself.

Both scenarios allow 4 decimals, so I don't know which is which - there should be a guide thing on that web site somewhere. Hope that helps.