We thank Mr Sia Cheong Yew for his letter ("Relook trading amounts on low-priced stocks"; Dec 30, 2016).

Partial completion of an order can occur when an investor on one side of the transaction completes his own order, but does not have sufficient quantity to match the full amount placed by another investor on the other side of the transaction.

This is present in stock markets across the world, including Australia, Hong Kong, Malaysia, Thailand and the United States.

If an investor wants to avoid partial completion of a full order size, he can utilise the "fill-or-kill" order type which allows the entire order to be cancelled should the total order quantity not be immediately fulfilled.

The Singapore Exchange's trading engine does accept "fill-or-kill" order types and there are brokers and trading platforms in Singapore which offer customers the use of this order type in their trading platforms.

Investors may consult their brokers on the availability of the "fill-or-kill" order type as well as other alternatives offered, to more actively manage orders and avoid similar experiences.

We understand that minimum commission rates vary among broking firms, platforms and service offerings.

While we appreciate that the brokerage fee charged was disproportionate to the small partial completion of Mr Sia's order, these commission rates are not determined by SGX.

Investors are encouraged to provide their brokers with feedback should a resulting transaction size be uneconomical.

Nico Torchetti
Head of Market Services
Singapore Exchange