Sustainable Technology Patent Litigation Confirms a Doctrine of Equivalence in the UPC

A recent decision of the Court of First Instance of the Unified Patent Court (UPC) relating to microbial fuel cells sets out the test for assessing infringement by equivalence at the UPC.

The case was centred around Plant-e’s European Patent EP2137782, which is directed to a plant microbial fuel cell (P-MFC). The case revolved around claim 11 of the patent, which recites a method for converting light energy into electrical energy and/or hydrogen, using a living plant and micro-organism:

11. Method for converting light energy into electrical energy and/or hydrogen, wherein a feedstock is introduced into a device that comprises a reactor, where the reactor comprises an anode compartment (2) and a cathode compartment and wherein the anode compartment comprises a) an anodophilic micro-organism capable of oxidizing an electron donor compound, and b) a living plant (7) or part thereof, capable of converting light energy by means of photosynthesis into the electron donor compound, wherein the microorganism lives around the root (8) zone of the plant or part thereof.

The living plant of the claimed system provides a sustainable source of electrons to micro-organisms in the system, enabling the production of energy. Infringement proceedings were commenced by Plant-e, asserting infringement by Arkyne Technologies’ (referred to as “Bioo”) products. Bioo requested that Plant-e’s claims were dismissed, and that the patent in question was revoked.

Bioo’s products were directed to double-layer biobatteries, capable of producing electricity by feeding on natural soil, with the use of plants. Unlike Plant-e’s claimed method, Bioo products have a soil layer between the plant roots and microorganisms, which are in a separate compartment. Bioo’s product allows nutrients to leach to the microorganisms through rainwater and irrigation, thus providing organic matter to the microorganisms from the plants.

The court concluded that the patent in question was valid, but not infringed based on a literal interpretation of the claims. Having reached this conclusion, the court then considered whether infringement by equivalence should be considered. Although the UPC Agreement (UPCA) itself does not contain a provision on the doctrine of equivalence, the court noted that the Article 2 of the Protocol on Article 69 EPC makes it clear that equivalents must be considered when assessing the scope of protection.

Having established that infringement by equivalence should be assessed, the court set out the following four step test:

1. Technical equivalence: does the variation solve (essentially) the same problem that the patented invention solves and perform (essentially) the same function in this context?
2. Fair protection for patentee: is extending the protection of the claim to the equivalent proportionate to a fair protection for the patentee?
3. Reasonable legal certainty for third parties: does the skilled person understand from the patent that the scope of the invention is broader than what is claimed literally?
4. Is the allegedly infringing product novel and inventive over the prior art?

On the question of technical equivalence (1), the court considered post-published data on Bioo’s system provided by Plant-e. The court concluded that Bioo’s system was technically equivalent to the teaching of the patent, having the same function and solving the same problem. The only differences between Bioo’s system and the claimed method were not considered to affect the function.

When considering fair protection (2), the court noted that the patented method represented a new category of microbial fuel cells. Therefore, a “fairly broad scope of protection” was considered to be commensurate with the patentee’s contribution to the art. In these circumstances, the extension of protection to equivalents was considered to be both appropriate and proportionate. It remains to be seen how the court will assess this second question for patents that do not represent an entirely new category of innovation. However where this is the case, it seems to present a strong argument for applying a doctrine of equivalence at the UPC.

In relation to the question of ensuring legal certainty for third parties (3), the decision sets out that the requirement of legal certainty is met if the skilled person:

“understands that the patent claim leaves room for equivalents because the teaching of the patent is (clearly) broader than the wording of the claim and there is, still in the eyes of the skilled person, no good reason to limit the scope of protection of the claim.”

In the present case, the court considered the teaching of the patent to be the addition of a plant to an MFC to provide feedstock to make the MFC independent of externally provided feedstock. The court considered that Bioo’s product was another way to achieve the same result, and that the patent leaves room for equivalents.

This test further highlights the importance of considering and – where appropriate – contesting description amendments proposed by the EPO prior to grant. The test considers legal certainty on the basis of whether the teaching of the patent is broader than the wording of the claim. Therefore, the deletion of embodiments that may capture equivalents but do not fall within the literal claim scope could have a negative impact on the outcome of the third stage of the test for equivalence in UPC proceedings.

The final step of the test is to assess whether the allegedly infringing system would have been novel and inventive at the priority date of the patent in question. The purpose of this final stage is to assess whether the alleged infringer has a Gillette/ Formstein defence available. Briefly, these defence essentially argue that the alleged infringing product lacks novelty or inventive step in view of the prior art, and thus a finding of infringement must also result in a corresponding lack of novelty or inventive step.

This decision from the UPC appears to be good news for patentees, confirming that a patent may be enforced via the doctrine of equivalence at the UPC, providing that the requirements of the four stage test are met. However, it also highlights the importance of considered drafting and prosecution, to increase the likelihood of the courts finding that the requirements of the four-step test are met.