특허침해 판단시 기능식 청구항의 해석

Functional claim uses the language of function to partially define the subject matter of an invention. The US Patent Act gives special treatment to a functional claim. According to 35 U.S.C. §112 ∏6, “An element expressed means-plus-function in a claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.” However, the Korean Patent Act does not have a provision corresponding to 35 U.S.C. §112 ∏6. The Korean Supreme Court does not have a unified opinion on the interpretation of a functional claim in determining infringement. For example, some Korean Supreme Court Cases limit the functional claim to the embodiment in the specification but some Cases do not. I insist that the interpretation of the functional claim should be conducted to cover the corresponding structure, material, or acts described in the specification plus something obvious from the structure, material, or acts because the embodiment in the specification and something obvious from the embodiment are the parts which were made public from the functional claim. So the interpretation of the functional claim operates more like the reverse doctrine of equivalents rather than the doctrine of equivalents because it restricts the coverage of the literal claim language. However, the doctrine of equivalents should be used for the interpretation of a functional claim when the claimed function is not literally found in the accused product and the accused product was developed after the patent was issued.