Korea Exchange (KRX)
Limit-on-Close (LOC) & Limit-on-Open (LOO) Buy/Sell→ShortSell
Market-on-Close (MOC) & Market-on-Open (MOO) Buy/Sell→ShortSell
Basic Market Rules
Lot Size: 10 shares (1 share if base price of the issue on that day is above KRW 50,000).
Tick Size: up to KRW 1000 = 1 ; 1000 to 5000 = 5 ; 5000 to 9990 = 10; 10000 to 49950 = 50; 50000 to 99900 = 100; 100000 to 499500 = 500; greater or equal to 500000 = 1000.
Daily Price Limit: the current price limit in the KOSPI market is 15% for stocks, KDRs, and ETFs.
Short Sale Rules: short selling is permitted subject to restrictions and regulations. Short sales should be reported as such to the exchange. All short sales must be executed on the uptick.
Circuit Breakers: all trading shall be suspended if KOSPI decreases continuously for 1 minute by more than 10% of the closing price of the previous day. Once circuit breakers is exercised, a suspension occurs for 20 minutes. The KRX resumes trading 20 minutes after the issue of circuit breakers. The first price shall be formed in single price for 10 minutes from resumption and then crowd trading shall be applied.
Periodic Call Auction
The Periodic Call Auction is a method of trading to be used when it is necessary to form price balance through the concentration of demand and supply. It receives offers and bids for a certain time and then trading is concluded in a single price with priority among offer prices in accordance with price-time priority.
Quantity Allocation in Periodic Call Auction when opening price is formed in the upper or lower limit price
In case of Periodic Call Auction, trading is concluded according to price-time priority, but as far as opening price formation in the upper or lower limit price, the allocation of concluded quantities shall be made in sequence from the largest quantities of an offer price to the smallest ones on the basis of quantity priority (see the following list), while allocation in other cases shall be made in time priority.
10 times of trading quantity unit
50 times of trading quantity unit
100 times of trading quantity unit
200 times of trading quantity unit
half of balance (quantity below the said unit shall be rounded off to the nearest integer)
If the opening price is determined as KRW20,150 (the upper price limit), for instance, quantities at the selling offer price shall be allocated according to quantity priority between buying offers at the upper price limit.
The single price auction determines the closing price on KOSDAQ using price-time priority.
Market on Close orders are treated as priced at most recent market price. If there are more aggregated offer market orders, the market on close orders are treated as priced at one tick lower than the most recent market price. If there are more aggregated bid market orders, the market on close orders are treated as priced at one tick above the most recent market price.
The total quantity of offer order priced lower than the match price (closing price) and the total quantity of bid order priced higher than the match price is matched and executed.
For orders quoted at the match price, the total quantity of either bid or offer quotation is matched. Of the quantity in excess of the quantity of the other side, the quantity in excess of the quantity of the trading unit of the concerned issue is matched.
In cases where there are more than two matched prices, the price that is equal to the most recent market price shall be the match price. If there is no price that is equal to the most recent market price, the price that is closest to the most recent market price shall be the match price.
Order input period (14:50 - 15:00): if the reopening of the market falls within 20 minutes before market closing time (15:00). The order acceptance period for the closing auction is from the reopening time to the market closing time.
Order matching (15:00)
Limit order with TIF set to DAY
Market order with TIF set to DAY
Market on Close order with TIF set to DAY
For more information on the rules governing the KRX auctions and trading, see the Regulations page.