In general, trading of exchange products takes place in three periods: opening
period, free period and closing period.
In addition, a closing price trading takes place in Equites section.
In respect of the opening and closing periods of trading, the most important
role is the determination of the official opening and closing prices of the listed
products.
In the order collection subperiod, the orders are entered into the Order Book,
but no transaction is made. During this period, on the basis of the orders in
the Order Book, the system continuously displays a so-called indicative price,
which is the equilibrium price (opening or closing price) established according
to the actual status in the book. After each newly entered or withdrawn order,
the system updates the indicative price. After the closing the order collection,
no more orders can be made from the data entered until such time that, on the
basis of a set algorithm, the determination of the product’s opening or closing market price is determined.
In the free period, transactions are made with continuous matching of the orders.
An order arriving to the Order Book shall be immediately transacted if there is
a counteroffer (in the case of a buy, an ask, in the case of a sell, a bid), corresponding
to its price. If there is none, the order will be held in the Order Book until
the expiry of the time-line set, ranked by price and timing priority. Price priority
shall be understood, in the case of buy orders, as the order with the higher price
and, in the case of sell orders, the one with the lower price. An order made at
an identical price, but earlier in time shall have a priority against the order
made later.
In the closing price trading period transactions are concluded according to continuous
matching algorithm, solely on the closing price of the security determined on
that trading day.
In case the official closing price has not been determined, transactions cannot
be concluded in the closing price trading period. Orders in the Order Book are
accepted only at the closing price, too. As all orders in the Order Book are at
the same price, therefore they cannot be prioritized by price, so all active orders
shall be macthed accoording to time priority.