Spoofs, Icebergs and Reloading Orderseric

This is part six of the ASX order book series. So far we've treated the order book as information: protection behind you, a clear path ahead, a surplus in the opening auction. All of that assumes the orders you see are real.

They aren't always. The journals I read were full of moments where a trader leaned on a wall that vanished, or fought a seller who turned out to be far larger than the visible size. Learning to read behaviour rather than displayed size was one of the clearest markers of progress over time.

Three ways the book misleads you

A quick note on legality. Placing orders you intend to cancel in order to create a false impression of supply or demand is market manipulation, and it's illegal in Australia. That doesn't mean it never happens, especially in small, thin stocks, but it does mean regulators take it seriously. Icebergs and reloading orders, on the other hand, are perfectly legitimate ways for large participants to avoid moving the price against themselves.

Fake size: how to tell if a wall is real

You can't know the intent behind an order. You can observe how it behaves.

Does it hold when price arrives? The single most useful test. A genuine large bid gets hit when sellers come down to it, and the prints show volume trading at that price. A spoof disappears one or two ticks before price reaches it.

Does it move with price? Some large orders creep up or down a tick at a time, staying just out of reach. That's an order that wants to influence, not to trade.

Does it appear at convenient moments? A huge offer that materialises right when a stock starts to run, and vanishes when the run stalls, is designed to scare buyers off.

Is it out of proportion? An order worth many times the stock's typical daily turnover, sitting in a quiet small cap, deserves suspicion.

The practical consequence for protection is simple: don't trust a wall until you've seen it absorb volume. A wall that has already been hit and is still there is much more meaningful than one that has never been tested.

Hidden size: icebergs and reloading orders

The opposite problem is more dangerous for intraday traders. A large seller who needs to move a big line doesn't want to show it, because the moment they do, everyone gets out of the way. So they show a small piece. When it's filled, another small piece appears at the same price. And again. And again.

On the tape, this looks like far more volume trading at one price than was ever displayed there. On the depth, it looks like an offer that never quite goes away, no matter how many buyers hit it.

The journals described this in plain language: a seller "reloading the offer" all day. One recurring observation was that such a seller is telling you something important: someone big wants out at this price. That's not an environment for a long scalp. The stock can only move up once that seller is finished.

The release: when the big order finishes

Here's where the opportunity is. A reloading seller caps a stock. Every buyer runs into them. Then, at some point, the seller is done. The offer at that price is hit, and nothing reappears.

What happens next is often fast. All the demand that was being absorbed suddenly has nothing to absorb it, and price can jump several ticks very quickly. Traders who were watching the level, patiently, can buy the moment the reload stops. Traders who were fighting the seller have often given up by then.

The same works in reverse: a large hidden buyer supporting a stock at a level, and the moment they stop, the floor disappears.

Some traders will even hold a position specifically for this: waiting for a large seller at a round number to finish, expecting the stock to move through the level once they do. That takes patience, and it can take days rather than minutes for a really large line.

Fragmentation: the book you can't see

Australian equities trade on more than one venue. A meaningful share of volume can trade away from the ASX order book, and broker algorithms can hold size that isn't displayed anywhere. Orders on different venues don't always interact the way you'd intuitively expect, especially around the auctions.

For intraday traders the practical points are:

• Use a consolidated view of depth if your platform offers one.
• Remember the ASX auctions (open and close) are where the official prices are set, and where depth matters most.
• Treat the visible book as a sample of intentions, not the full picture.

Practical rules

Distilled from the journals, here's how the experienced traders handled a book they couldn't fully trust:

The next post covers what happens after you're in: how to tell when the tape has stopped confirming your trade, and why the best scalpers exit on time as much as on price.