The claim is generally drafted in a form of ‘(…) according to (…) (preamble), wherein (…) (feature part)’, where the examiner regards the preamble as disclosing the known technology according to the examination practice.

The Supreme Court ruled as follows as to whether the constitutions 1 to 4 disclosed in preamble are the known technology, in the utility model right nullification trial for a screen device (sieve shaker) to filter residues and suspended materials contained in wastewater before entering a collection tank at industrial wastewater treatment plants (Supreme Court Ruling 2013 hu 37, January 19, 2017).

(Prosecution History)

Among the constitutions 1 to 4 in preamble, while the constitution no. 4 was the main feature in the argument, the utility model right holder amended the constitution no. 4 mistakenly to be preamble regarding it as a known technology.

(IPTAB & Patent Court)

The inventive step of the utility model was acknowledged in that constitution no. 4 was not regarded as known technology which cannot be easily construed by the skilled person from the prior art.

(Supreme Court Decision)

1) It is a matter of fact whether a constitution of the invention was known prior to the filing as to novelty or inventive step.

2) The party who argues lack of novelty or inventive step has the burden of proof whether such constitution was known.

3) Thus, such known fact needs to be proved by evidence in principle, unless the right holder admits or it is obvious fact without the need for proving before the Patent Court.

4) If it can be acknowledged the applicant included a certain constitution to the preamble of claims as a known technology beyond the simple background or conventional art considering the overall disclosure and filing history of the invention, it can be practically assumed as being known prior to the filing without additional evidence.

5) However, since such assumption is not absolute, the decision ruled such assumption may be reversed if there is special circumstance such as misrepresentation by the applicant in describing the technology as known skill which was a prior invention not published at the time of filing or known only within the company.

The decision made it clear the principle of estoppel is not applied when admitting the known fact during the filing process.