In a rare patent infringement case to go the distance in the Singapore courts, a lock maker, one Ng Kok Cheng, who has cornered almost half of the lucrative Housing Development Board (HDB) flat market with a patented lock has successfully sued a dealer for copying his lock’s design.

It was recently reported in the local press that dealer Chua Say Tiong was found by the High Court to have copied Ng’s two-bodied Duro lock as there was a "striking resemblance" between Ng’s Duro lock and Chua’s Castle lock. Judicial Commissioner Judith Prakash ruled that the Duro lock patent was a valid one and that Mr Chua's lock had infringed it. The assessment of damages will be heard later.

Mr Ng’s success with the Duro lock began in 1995 when he sought to improve the existing locks used on HDB gates. He finalised the design of the Duro lock in 1997. It consists of two bodies and a shackle bar which passes through one part of the body into the other. Its unique features are that it can clamp and stay on the gate and has two key holes. The latter feature allows the user to open the lock from the inside and the outside of his flat. Ng then applied for a patent, which was granted last August.

Last July, it came to Ng’s attention that Chua's Castle lock was being widely sold for about 15 to 20 per cent cheaper than the Duro lock. The Duro locks were being sold for $118 and $128. Upon inspection, Ng found the Castle lock almost identical to his.

Ng then sued Chua when he failed to respond to demands to stop the manufacture and sale of the Castle lock. Chua's lawyers argued that Ng's patent was invalid and the design concept of the Duro lock was an obvious one. The Judicial Commissioner however found that the Duro lock has unique features not found in other locks. She also said that the lock's success also goes "some way towards establishing the invention is not obvious".

The success of this suit for the inventor may well pave the way for increased activity in patent infringement litigation in the future, which would be a boost to the development of the local patent law regime.

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