How auctions work: the basics

Auctions are a widely accepted method for transparently and fairly defining the market price for financial products.

Investors can bid (to buy) or offer (to sell) financial products at auctions.

The final price of financial products is determined by the total supply and demand from buyers and sellers at each auction, except where a fixed price is stated.

No trades are completed until the end of the auction and all buyers and sellers pay or receive the same fair price for the financial products.

Trades are allocated to successful auction participants, using our simple priority queue.

Bids and offers

Currently you can choose between submitting a ‘limit order’, or using our ‘auto bid’ or ‘auto offer' function.

Limit orders

Limit orders are a request to buy or sell the financial products at the specific price or a better price.

Limit bids

Limit bids are an offer to buy up to a maximum number of financial products, at the specified price or below.

Limit offers

Limit offers are an offer to sell up to a maximum number of financial products, at the specified price or above.

This means buyers will never pay more than their bid price, and sellers will never receive less than their offer price - but both buyers and sellers have the potential for a better price than their bid or offer.


When you submit a limit order, your best price is submitted into the order book immediately. All orders are anonymous, but other investors can see someone is willing to buy or sell the specified number of financial products at the specified price in your limit order.

Auto bids and auto offers

Use the auto bid or auto offer function to automatically improve your bid or offer, if it is outbid, up to your specified best price.

When you submit an auto bid or auto offer, your price is submitted as a standard limit order. If your price is outbid, it is automatically withdrawn and re-submitted at incrementally better prices, up to your specified best price. This means your best price won’t necessarily be submitted immediately into the order book – only the price that is sufficient for your order to trade to the maximum extent possible.

If there are no existing orders that your auto bid or auto offer could trade with, nothing is submitted into the order book until there is an order it can trade with. If your auto bid or auto offer is outbid at its best price, it will remain in the order book at its best price, unless you withdraw it, as new orders could be submitted that allow your order to trade in whole or in part.

Investors only see the limit orders that are actually submitted into the order book. No one else sees the details of your auto bid or auto offer best price.


The pros and cons of auto bids and auto offers

Auto orders allow you to ‘set and forget’. There’s no need to log in to the auction when it’s closing to try to outbid other investors.

If you submit an auto order, a later limit order at the same best price may take priority over your order if the price submitted into the order book for your auto order had not reached your best price before that limit order was submitted.

Auto orders can help to avoid disorderly pricing that could result from an investor submitting a very aggressively priced order – the investor is likely to receive better pricing and there are less likely to be unfair price fluctuations using auto bid and auto offer. For this reason, if you wish to submit a bid to buy financial products at a price much higher than the expected price, or you want to offer to sell financial products at a price much lower than the expected price, we may require this to be done by an auto bid or auto offer rather than by a limit order. Don’t worry – other investors won’t be able to take higher priority by submitting a limit order, because we will require all investors to use auto orders based on the same thresholds.

For more technical information on the order book and how a ‘fair’ price is calculated, have a read of our technical information page on how auctions work.

The auction process


Auction pre-open

Businesses on the Catalist Public Market are required to provide comprehensive information before each auction, so that investors have everything they need to make good investment decisions.

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Auction open

When an auction is open, investors can submit bids (to buy) and offers (to sell) the relevant financial products. Investors can also amend or cancel bids and offers, during this period.

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Auction pre-close

During the pre-close period, only investors who submitted a bid or offer in the open period can improve their bid or offer – no new bids or offers are allowed and orders cannot be reduced or cancelled. This allows investors to react to any late bids or offers, with the knowledge that those bids and offers can’t be cancelled at the last moment.

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Auction closed

Provisional auction results are made available after the auction has closed. Investors with successful bids or offers are legally obligated to complete their transaction and we may complete the transaction on their behalf.

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Interested in reading about the more technical side of our auction process?

Learn more