Matching of odd-lot trades will proceed by call auction every three minutes from 9:10 am, except securities for which extended matching intervals have been implemented under the bylaws or rules of the TWSE.
In principle, odd-lot trades are matched based on price priority and time priority, and the priority for satisfying trading orders is governed by the following principles:
At the end of the time for placing after-market odd-lot trading orders, the trades will be matched by call auction. The sequence of executed trades reported shall be determined by the price priority principle. For reported trades of the same price, the sequence shall then be determined in a random order determined by computer. t.
- Price priority principle: higher-priced buy orders shall have priority over lower-priced buy orders. Lower-priced sell orders shall have priority over higher-priced sell orders. Where orders are placed at the same price, priority shall be based on time priority principle.
- Time priority principle: For orders placed prior to the first matched trade, priority shall be determined randomly based on computer arrangement. For orders placed after the first matched trade, priority shall be made on the order in which the orders were placed.