Singapore Patent Infringement – The purposive approach as defined in Kirin-Amgen upheld

Since the signing of the Free Trade Agreement (U.S. – Singapore Free Trade Agreement) in May 2003 between Singapore and the United States, exports from the United States to Singapore have “exploded”, and trading between both countries has increased substantially in the years succeeding the signing.

Due to the specific nature of intellectual property rights (IPRs), a proper outlook needs to be taken in how to effectively protect each individual IPR one holds. We are well aware of the special territoriality issue of the IPRs; and as a specialist in this field in Singapore, need to advise our clients accordingly to enhance the strength of the rights they have in trades.

Take for instance, the patent infringement analysis/ judgment adopted by the Courts. In the United States, the Courts generally adopt the ‘doctrine of equivalents’, namely, if the defendant’s product performs substantially the same function in substantially the same way to yield substantially the same result, the defendant’s product will be judged falling within the claimed scope of the patentee’s patent, i.e. it infringes the patentee’s patent, under the general principle to stop third parties to unjustly take advantage of the patentees’ benefits.

However, in Singapore, the ‘purposive approach’ adopted by the Singapore Courts in appraising patent infringement is different from the U.S. ‘doctrine of equivalents’. In brief, Singapore Courts are pro British and European principles that hail from Lord Diplock’s judgment in Catnic Components Ltd v. Hill & Smith Ltd ([1982] RPC 183, [1983] FSR 512). A re-formulation of the purposive approach was give in Improver Corporation v. Remington Consumer Pte Ltd ([1990] FSR 181), and was further confirmed in Kirin-Amgen Inv v. Hochst Marion Roussel Ltd ([2005] RPC 9). The essence may be addressed to duly construe any element which is equivalent to an element specified in the claims. In line with this, in Singapore case Bean Innovation Pte Ltd & Anor v. Flexon (Pte) Ltd ([2000] SGHC 219, [2001] 3 SLR 121 (CA)), a patent for a mailbox assembly with a central locking system for individual mailboxes, where its central locking system served to prevent junk mail from being delivered into the mailboxes; was infringed by the defendant’s mailbox that also had a central locking system which achieved the same results. The patentee argued that there was infringement because the defendant’s product performed the same function as the patented product. The Court identified the ‘matrix of orthogonal bars’ as the most essential feature in the invention whereas the defendant’s mailbox did not have this particular feature. Instead, it used stopper screws to do the locking and unlocking. The Court’s conclusion was that there was no infringement, even though the product performed the same function as the patented product.

The Singapore Courts adoption of the UK position is understandable given the common law in Singapore flows from English common law and UK decisions have always had persuasive if not binding effect here. It is therefore important for patentees to be aware that the approach of the Singapore Courts in respect of the test for infringement would be to follow the “purposive approach” as adopted in the UK and not the “doctrine of equivalents of adopted by the US Courts. This difference is important for the patentee in assessing their position when considering whether there has been infringement of their patents or not.