SINGAPORE - A property agent has become the second person to be penalised under the "Do Not Call" rules which kicked in on Jan 2.

Kuan Chow Sheng, 32, sent messages advertising three residential property developments - two in Singapore and one in London - to numbers listed on the Do Not Call Registry, which has more than 600,000 numbers. The rules ban firms from marketing to any number listed on the registry without first getting consent.

On Monday, Kuan was fined $27,000 - or $3,000 per charge - after pleading guilty to 9 of 27 offences committed between Feb 8 and March 2, with the rest taken into consideration.

The court heard that Kuan used a SMS broadcasting software known as "BluOcean" to send the messages to a list of contacts he had accumulated over the years in the real estate industry. The messages were sent with nine Singapore telephone numbers subscribed to on Kuan's behalf by relatives and personal friends, though he did not tell them the numbers would be used for his telemarketing activities.

Between Feb 8 and March 2, the Personal Data Protection Commission received 233 valid complaints about Kuan from people on the registry.

Pleading for leniency, Kuan's lawyer said his client was the sole breadwinner in a family of five, including three young children, and had acted in a "moment of folly". He was unable to focus at the time due to his wife's health issues, Kuan's lawyer added.

Deputy Public Prosecutor Jane Lim called for a fine of not less than $3,000 per charge, to deter others engaged in telemarketing activities from not checking the registry before sending messages, so as to protect the private space of individuals.

Ms Lim added that Kuan's industry, the real estate industry, was responsible for the highest number of complaints since the rules kicked in. This made up about 47 per cent of all complaints.

Anyone convicted under the Personal Data Protection Act could be fined up to $10,000 per charge.