In another case in the Pemetrexed saga, which we last reported on in March 2019 (see links below), the Hague Court of Appeal has overturned the earlier decision of the District Court and set the Dutch approach to equivalence in patent infringement cases.

As a brief recap, claim 1 of Eli Lilly’s patent requires vitamin B12 + Pemetrexed disodium and claim 2 requires vitamin B12 + Pemetrexed disodium + folic binding protein.

The potential infringer, Fresenius, used a composition including Pemetrexed tromethamine in place of Pemetrexed disodium.

The first instance decision at the District Court of The Hague determined that Fresenius did not infringe Eli Lilly’s patent. This decision was in contrast with that in many other European jurisdictions including the UK, Germany and France.

The Court of Appeal first noted that Article 69 European Patent Convention and its Protocol, which relate to the scope of protection conferred by a European patent, must be applied. Section 1 of the Protocol states that a position must be taken that “combines a fair protection for the patent proprietor with a reasonable degree of legal certainty for third parties”, and Section 2 states that “due account shall be taken of any element which is equivalent to an element specified in the claims.”

Previously Dutch courts had used a one-step test in applying the Protocol, and whilst the Court of Appeal in this case did not reject the one step approach, they used a two-step approach which is much more consistent with that taken in other European jurisdictions.

The two step test was:

  1. Does the accused product conform to all features of the claim?
  2. If not, were the differing features equivalent to the claim features?

Clearly, the first step was not met and therefore the court proceeded to assess the second. The court set out four principles to consider when assessing the second step:

  1. The differing feature must be technically equivalent to the claimed feature
  2. From the point of view of fair protection for the patent proprietor, it must be appropriate to take into account equivalents when determining the patent’s scope of protection.
  3. Next, protection by way of equivalence must not be at odds with the reasonable degree of legal certainty due to third parties.
  4. Lastly, in appropriate cases it must be examined whether the allegedly infringing product is novel and inventive in relation to the prior art.

Considering the first principle, the Court determined that the function of the two salts (Pemetrexed disodium and Pemetrexed tromethamine) was technically equivalent – the function was to neutralize Pemetrexed anions to make the composition suitable for storage and sale.

Turning to the second principle, the Court noted that Eli Lilly’s patent encouraged the skilled person to search for alternative salts.

On the third principle, the Court of Appeal stated that both the patent itself and the prosecution history gave no grounds for the skilled person to believe the patent was limited to Pemetrexed disodium. The district court differed on this point and had stated in their decision that the limitation to Pemetrexed disodium was a conscious limitation made during prosecution of the Lilly patent application. The Court of Appeal disagreed as the limitation was brought in to overcome an added matter objection. The Court of Appeal further noted that the fact that the inclusion of equivalents during prosecution would be added matter does not prevent protection for the equivalents.

Finally, the fourth principle was found not relevant since Fresenius had been granted a patent for its invention.

The Court concluded that Eli Lilly’s patent was infringed by Fresenius and, perhaps more importantly, the Court set out a clear approach to equivalence in the Netherlands which is more in line with that of other European jurisdictions.

To read our related articles please use the links below:

March 2019 –

March 2019 –

November 2018 –

November 2017 –

July 2017 –

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 Our news articles are for general information only. They should not be considered specific legal advice, which is available on request.


Our articles are for general information only. They should not be considered specific legal advice, which is available upon request. All information in our articles is considered to be accurate at the date of publishing.

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