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Singapore – Landmark Patent Revocation by IPOS under Section 80 of the Patent Act

Cargill International Trading Pte Ltd v Martek Biosciences Corporation [2009] SGIPOS 12


On 20 January 2006, Cargill International Trading Pte Ltd (the Applicant) filed an application with the Intellectual Property Office of Singapore (IPOS) to revoke the Singapore Patent No. 42669 entitled “Arachidonic Acid and Methods for the Production and Use thereof” owned by Martek Biosciences Corporation (the Patentee). The applicant is a subsidiary of Cargill Inc, a multinational corporation based in the US with business that primarily focuses on the production and marketing of food and agricultural commodities and related products and services. The Patentee is also a US based company which focuses on R&D of nutritional products and in particular licensing of nutritional supplements such as ARA and DHA for use in infant formulation.

This is the first patent to be revoked by IPOS under Section 80 of the Singapore Patent Act (CAP 221). Section 80 provides an exhaustive list of grounds whereby a granted patent can be revoked in Singapore. In this revocation proceeding, the Applicant has alleged that the invention as claimed is not patentable and lacks enabling disclosure pursuant to sections 80(1)(a) and 80(1)(c) of the Patent Act respectively. However, the ground under section 80(1)(c) was not pursued further prior to the Hearing. Nevertheless, the Applicant succeeded in revoking the Patent under Section 80(1)(a) of the Patent Act.

Background of Patent

The SG 42669 Patent is the Singapore National Phase Application of the PCT International Application number PCT/US96/00182, filed on 3 January 1996 and claiming priority from its US priority application No. US 08/367,881 dated 3 January 1995. The PCT application was entered into national phase in Singapore on 2 July 1997 as Singapore application No. 9703038-1, and was subsequently granted on 30 March 1999.

The subject matter of SG 42669 relates to the production and use of fungi derived oil containing arachidonic acid (ARA), which is essentially free from eicosapentaneoic acid (EPA). It also discloses compositions containing high amount of ARA in triglyceride form, and the use of such oils in nutritional and cosmetic products. In a preferred embodiment, the fungi, M. Alpina is cultivated under conditions that produce triglyceride oil having high levels of ARA. The fungal biomass is subsequently harvested and the oil is extracted, recovered and used as an additive for infant formulation.


The Patentee submitted amendments to the patent claims on 6 September 2006 pursuant to Section 83 of the Patents Act and rule 80(3) of the Patents Rules. The amendments were subsequently advertised on 30 October 2006 in the Patents Journal No. 200610A without any further opposition was accepted after the prescribed opposition period. The amendments were allowed, as they did not result in the specification disclosing any additional matter nor extending the protection conferred by the Patent.

Both parties had also attempted inter-parte negotiation between September 2007 and April 2008, but were unsuccessful and a Case Management Conference was convened on 28 April 2008 where the Registrar subsequently directed for the Patent to be re-examined.

Reliance on Foreign Decision

To support their application, the Applicant has also submitted opposition decisions of foreign corresponding application from USPTO and EPO where similar patents belonging to the Patentee were being challenged. However, the Patentee pointed out that the decisions have not been finalized and the claims and material facts surrounding those decisions were different from those of the present patent in Singapore. The Registrar agreed with the Patentee’s reasoning and relied on the decision in the First Currency Choice Pte Ltd v Main-Line Corporate Holdings Ltd and Anor Appeal [2007] SGCA 50. As such, they did not place much reliance on those foreign decisions.

Patentability Assessment

In determining the novelty of an invention, the guiding principles as set out in Trek Technology (Singapore) Pte Ltd v FE Global Electronics Pte Ltd (No. 2) [2005] 3 SLR 389 were followed. To destroy novelty, the prior art must unequivocally point to the invention and must not merely be a signpost on the path to discovering the invention. The disclosure must be “enabling” i.e. sufficient so as to enable the skilled addressee to put the invention into practice. For a prior publication to anticipate the patent, it must be established that following the teachings in the prior publication would inevitably lead to the invention covered by the patent. The prior disclosure must not only identify the subject matter of the claim in the later patent, it must do so in a way that enables the skilled man to make or obtain it: at [71] – [73]. In this case, some of the claims in the invention were found to have been anticipated by prior art and hence were not novel.

For the assessment of inventive step and the identification of the inventive concept, the Registrar has applied the principle test laid down by Windsurfing International Inc v Tabur Marine (Great Britain) Ltd [1985] RPC 59. One is allowed to combine documents or “mosaicing” to ascertain inventive step of the invention. However, it must be likely that the skilled person would have considered those teachings together: at [76]. In this case, the prior art cited were allowed to be combined and compared with the claims. The invention was found to be lacking in inventive step in view of the cited prior arts.

Expert Evidence

During the hearing, both parties presented their expert witnesses. An expert witness can, inter alia, explain words or terms of science or art appearing in the documents presented in the Court and give expert assistance to the court. The testimonies of the expert witnesses for the Applicant were from Puah and Nga, while those for the Patentee were from Barclay and Kyle. However, the testimonies of expert witnesses from both parties were considered to be of limited reliability for various reasons.

One of Cargill’s expert witness, Puah, who self-admitted that his expertise was not in the area relevant to the case at hand, and hence was determined to be not helpful in providing expert opinion. As for the other expert witness, Nga, who admitted during cross-examination that his evidence and conclusion were made with the benefit of hindsight after reading the Patent in question. His testimony was thus considered to be unreliable.

As for Martek, both Barclay and Kyle were in one way or another associated with the Patentee. Barclay is the Director of Discovery and Chief Intellectual Property Officer of Martek and hence is considered to have an interest in the proceedings. Although that does not prevent Barclay from giving evidence, his evidence was scrutinized with greater care and Barclay’s testimony was limited to only the technical and scientific aspects of the invention as such. Martek’s other expert witness, Kyle, is the inventor of the Patent in question. His clear explanations on the technical and scientific aspects of the technical field surrounding this invention were acknowledged, as those are factual statements. Considering that Kyle is the inventor of the disputed Patent and former employee of the Patentee, the Hearing Officers similarly had also scrutinized his testimony and limited their consideration of Kyle’s testimony to the technical and scientific aspects as such.

Patent Re-Examination

The Registrar has instructed for the SG 42669 patent to be re-examined to determine the validity and patentability of the invention. The Patentee had earlier submitted amendments to narrow the claims prior to re-examination. However, the Examiner found that the amended claims failed to overcome the novelty and inventive step objectives in view of the cited prior arts as Claims 1, 3, 12-13, 15-19 lack novelty and inventive step while Claims 2, 3, 35 and 36 also lack inventive step. Therefore, the Examiner concluded that the SG 42669 patent lacks novelty and inventive step, and should therefore be revoked.

In view of the result of the re-examination decision, the Registrar ruled that Martek’s SG 42669 Patent was invalid and that Cargill has succeeded in its application to revoke the patent on 3 November 2009. Accordingly, the Registrar ordered that the Patent be revoked in its entirety pursuant to sections 80(1)(a) of the Singapore Patents Act.