The Reason Why – Indulge Me if You Already Know
Pre-open this morning, have you noticed 839 shares on the buy side and 838 on the sell side—nearly identical volumes sitting at different price points. I’m not sure if everyone’s across this, but indulge me while I clarify what’s likely going on.
This kind of micro-lot behaviour is almost always algorithmic.
It’s not retail. Market makers and trading bots use these tiny orders to test depth, influence the indicative open price, and, most critically, to secure queue priority at specific levels.
During the ASX pre-open (7:00–10:00 am), no trades execute. Orders are simply gathered to calculate the opening price based on maximum executable volume.
By placing small, precise lots like 839 or 838, these systems can quietly anchor themselves in a favourable position for when matching begins—often without any intention of those trades ever executing.
It’s subtle, strategic, and a great example of how sophisticated modern price discovery has become, even before the market officially opens.
(20min delay)