Defences to Patent Infringement in Singapore

Last updated on December 14, 2023

In the event that you are sued for patent infringement, there are various defences which you may avail to in an attempt to avoid liability. These are found in the Patents Act (PA). The common ones are listed below.

Challenging the Validity of the Patent

This defence is commonly invoked as part of the “Gillette defence”, which is named after its successful invocation in a case involving the famous razor-making company. When employing the Gillette defence, the defendant argues that either the allegedly infringed patent is not valid, or that even if it is valid, there has been no infringement.

Challenging the very validity of the patent which is supposed to have been infringed is provided for in section 82(1)(a) PA and is commonly invoked in patent infringement cases. This is because if the allegedly infringed patent is not valid in the first place, there can be no liability for any infringement whatsoever.

By challenging the validity of the patent, it is being asserted that the patent should not exist on the register because it does not fulfil the requirements for registration. These requirements are namely that the invention to be protected by the patent are:

  1. Novelty;
  2. Involvement of an inventive step; and
  3. Capability for industrial application.

Read more about the requirements for an invention to be patentable in our other article.

Private and Non-Commercial Use

Under section 66(2)(a) PA, a patent will not have been infringed if the alleged act of infringement was done privately and for non-commercial purposes.

Experimental Use

Under section 66(2)(b) PA, there will not be infringement if the alleged infringing act is done for experimental purposes relating to the patented invention’s subject-matter.

Although the PA does not define “experiment” or “experimental purposes”, the English case of Monsanto v Stauffer Chemical Co has defined “experiment” as being “something done on a small scale having regard to the nature of the subject matter of the invention” and “is done for the purpose of finding out something about the invention rather than of proving or demonstrating commercial efficacy of a product to those who may be concerned with commercial use of the product”.

For example, trials carried out to test hypotheses can therefore be regarded as being for “experimental purposes”, but not trials which attempt to demonstrate to someone else that the product works.

Manufacture of Patented Pharmaceutical products to Support an Application for Marketing Approval

Under section 66(2)(h) PA, there will not be infringement if the alleged infringing act (e.g. manufacture of a product) is done in order to support the application of a pharmaceutical product for marketing approval. However, the making, using or selling in Singapore or the exportation outside of Singapore of products produced to support the application has to be related to meeting the marketing approval requirements. Otherwise, the manufacture of such product(s) will constitute infringement.

This defence is applicable to cases where a patent for a pharmaceutical drug is close to expiring and a competing manufacturer seeks regulatory approval for its generic version of the drug so that the generic drug may be released into the market upon the patent’s expiry. (Note that the generic drug cannot be marketed until the patent has actually expired, however.)

Specific Patient Defence

In relation to patented pharmaceutical products, under section 66(2)(i) PA, there will not be infringement if such products are imported, disposed or offered to be disposed for use by or on a specific patient in Singapore, or if such products are used by or on that patient. In addition,

  • The product has to be required for use by or on that patient;
  • The relevant authority has to have granted approval specifically for the import of that product for use by or on that patient; and
  • That product has to have been produced by or with the consent (conditional or otherwise) of the proprietor of the patent or any person licensed by him.
  • This defence also covers patents granted in any country outside Singapore in respect of the same or substantially the same product.

Prior Use Defence

Under section 71 PA, before the priority date (i.e. date on which the patent application for an invention is filed), if a person in Singapore has either:

  • Done, in good faith, an act which would constitute infringement of the patent if it were in force; or
  • Made, in good faith, effective and serious preparations to do such an act;

he is entitled to do or continue to do such an act notwithstanding the grant of the patent.

This defence provides such a person with a right to continue his existing commercial activity despite his jurisdiction being overtaken by the grant of the patent. In addition, the acts protected by the patent need not be exactly the same as the prior acts in order for the defence to be invoked.

However, the person protected under this defence may not grant a licence to another person to do the same acts. This defence also does not protect him in the event of expansion into other products and/or processes.

Innocent Infringement Defence

A defendant may rely on the defence of innocent infringement if they can prove that at the date of the infringement, they were not aware, and had no reasonable grounds for supposing, that the patent existed.

In such case, damages will not be awarded and no order may be made for an account of profits against the defendant as per section 69(1) PA.

Implied Licences to Repair

The repair of a patented product does not constitute patent infringement. This is because such repair does not amount to the making of the patented product, as held in the English case of United Wire v Screen Repair.

This article was written by Tan Siew Ann.