Swiss EBBO

An order is a binding offer to buy or sell a certain quantity of a security at an unlimited or limited price. Orders with the Routing Instruction "SEB" may be entered in or deleted from the hybrid order book orduring set periods. All incoming orders shall be assigned a time stamp and an identification number.

The Exchange supports the order type Normal order for hybrid trading. A Normal order may be entered by a participant at any time during the trading day. Non-executed parts of the order with Routing Instruction “SEB” in Swiss EBBO are moved to the Central Limit Order Book (CLOB) until they have been executed or deleted, or have expired. Other validities and routing instructions remain reserved.

A Normal order may be entered by a liquidity provider in the hybrid order book of Swiss EBBO at anytime during the trading day. Non-executed parts of the order remain in the order book until they have been executed or deleted, or have expired. Other validities and routing instructions remain reserved.

Trades are triggered by an incoming order from a participant with Routing Instruction “SEB” which is executed with the orders on the opposite side of the following order books provided quantity and price allow it

• Central Limit Order Book (CLOB);
• order book without pre-trade transparency SwissAtMid;
• hybrid order book Swiss EBBO.

In the case of an incoming order from a participant with Routing Instruction “SEB”, the Exchange determines which order book offers the best price on the opposite side and routes the order to the corresponding order book. If two or all the order books offer the same best price, the following priority applies for the first matching cycle:

1. order book without pre-trade transparency SwissAtMid;
2. Central Limit Order Book (CLOB);
3. hybrid order book Swiss EBBO.
   
   

The incoming order from a participant with Routing Instruction “SEB” is executed immediately taking account of the corresponding priority and the execution provisions of the corresponding order book with orders of the opposite side in SwissAtMid, CLOB and Swiss EBBO in one or more steps.

If an order with Routing Instruction "SEB" from a participant is only partially executed in the first matching cycle, the Exchange determines the next best price on the opposite side while taking account of the price limit of the order, whereby from the second matching cycle on only the Central Limit OrderBook (CLOB) and the hybrid order book Swiss EBBO are taken into account.

The partially executed order from a participant with Routing Instruction "SEB" is further executed in one or more steps, taking account of the corresponding priority and the execution provisions of the corresponding order book with orders of the opposite side in CLOB and in Swiss EBBO.

The execution of the order from a participant with Routing Instruction "SEB" continues in additional matching cycles until no more executions are possible in consideration of the participant's price limit. Subsequently the remaining portion of the order with Routing Instruction "SEB" from a participant is routed to the Central Limit Order Book. Other order validities remain reserved.

If the quantity of the order from a participant with Routing Instruction "SEB" is greater than the quantity of the order from a liquidity provider, and the liquidity provider has defined full execution quantity on his order, execution shall not take place in the hybrid order book Swiss EBBO.

If there are no orders from liquidity providers in the hybrid order book Swiss EBBO, the incoming order from a participant with Routing Instruction "SEB" is routed to the Central Limit Order Book (CLOB) or the order book without pre-trade transparency SwissAtMid.

The liquidity providers admitted by the Exchange provide prices on a best effort basis in the Swiss EBBO order book at the European best bid and offer (Swiss EBBO). The Exchange has appointed an independent service provider to determine the European best bid and offer (EBBO) and compares the prices provided by liquidity providers.

Trading in Swiss EBBO shall be interrupted if and for as long as:

• the relevant security is not in the trading period "Continuous Trading” on the Primary Reference Market in the Central Limit Order Book (CLOB) (i.e. Pre-opening, Opening, Closing Auction, Trading-At-Last or Post-trading); or
• trading in the relevant security on the Primary Reference Market in the Central Limit Order Book (CLOB) is interrupted (i.e. Delayed Opening, Stop Trading or Non-opening), or is suspended from trading.

If the price of the next execution in Swiss EBBO compared to the reference price on the Primary Reference Market in the Central Limit Order Book (CLOB) is outside a range determined by the Exchange (StopTrading), it will not be executed in the hybrid order book. The bandwidth (Stop Trading Range) for Swiss EBBO is determined by the trading segment on the Primary Reference Market of the relevant security, and is laid down in the corresponding annex to the "Trading Parameters" Guideline.

The liquidity provider may enter new orders for Swiss EBBO or delete existing ones during a trading interruption. Incoming orders with Routing Instruction "SEB" from participants are routed to the CentralLimit Order Book (CLOB) or order book without pre-trade transparency SwissAtMid during a trading interruption in Swiss EBBO.

Market control interventions remain reserved in accordance with the "Market Control" Directive.