LD Copenhagen on Sufficiency: The skilled person must be taught how, not Just what (UPC_CFI_560/2024, UPC_CFI_89/2025)

In its decisions in cases UPC_CFI_560/2024 and UPC_CFI_89/2025, the Unified Patent Court (UPC) confirmed that a patent must do more than describe a desired result. For claims defined by functional features, the specification must disclose a technical teaching enabling the claimed functionality to be achieved without undue burden.

The dispute concerned a hybrid generator system comprising a primary energy source and a battery. Claim 1 required a specific energy-flow arrangement where the generator used the primary energy source, such as an engine, to charge the battery, while electrical power supplied to an external output was provided exclusively by the battery. The subject matter of claim 1 therefore required that the primary energy source did not itself supply any electrical power to the output; its sole function was to provide charging energy to the battery.

The UPC found that the patent did not provide the skilled person with a technical teaching enabling this specific energy flow configuration. In particular, the patent did not disclose how to ensure that the energy generated by the primary energy source would only be used for charging the battery and could not be supplied directly to the output. The specification therefore failed to provide the necessary technical concept for achieving the claimed functional relationship between the primary energy source, the battery, and the output.

The Court acknowledged that technical solutions could theoretically be developed to achieve the claimed functionality. However, the mere fact that a skilled person could develop such a solution based on common general knowledge was not sufficient. The Court found that the patent specification did not disclose any such implementation, for example by specifying a switching sequence or another technical measure to control the energy flow.

The Court emphasized that the relevant question is not whether the skilled person could develop a solution, but whether the patent enables the claimed invention to be carried out without undue burden. Since the skilled person could not carry out the subject matter of claim 1 without undue burden, the Court concluded that the patent did not enable the skilled person to carry out the invention.

The decision confirms that an invention is sufficiently disclosed only if the patent specification provides the skilled person with at least one way of carrying out the claimed invention. In particular, in the case of functional features, at least one technical concept for achieving the claimed functionality must be disclosed. This approach is in line with the established practice of the European Patent Office (EPO). Although not considered in this case, the EPO also requires the “at least one way” to be performed across the whole range claimed in order to be sufficiently disclosed.