DSM IP Assets & ors v Algal Omega 3 Limited & ors [2026] EWCA Civ 136

The case concerned three patents (EP155, EP740, and EP801), each relating to microbial oils containing high levels of polyunsaturated fatty acids, such as the Omega-3 oil DHA, and their production.

At first instance, Mellor J held that:

  • EP155 was valid (and was conceded to be infringed if valid);
  • EP740 was invalid on several grounds; and
  • EP801 was invalid for obviousness.

The Second Defendant, Mara, appealed the judge’s decision of obviousness in respect of EP155 (arguing that the Judge had overlooked relevant evidence). The Claimants, DSM, appealed on two points of construction and the judge’s finding of obviousness in respect of EP801 (arguing there was no evidence to support the Judge’s finding) .

EP155 and EP801 both concern the extraction of microbial oils from a biomass.

The Court of Appeal dismissed both appeals. Although the overall teaching of EP801 concerned a solventless extraction process, the patent (and the claim) were found not to be so limited and the Judge’s construction was upheld. The appeal on EP155 and the appeal on EP801 concerning obviousness involved evaluative decisions and the Judge was not clearly wrong. DSM’s second construction appeal concerned the degree of precision with which numerical limits in the claim (specifically pH “8 or above”) were to be understood. This related to infringement only and in light of the outcome on validity this point was not determined.

Kyra Nezami acted as junior counsel for DSM.

[2026] EWCA Civ 136

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