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Kim & Chang Successfully Revokes Hair Bleaching Method Patent Both at IPTAB and Patent Court in Patent Cancellation Action


Kim & Chang successfully revoked the grant of a hair bleaching method patent (the “Subject Patent”) in a patent cancellation action both at the Intellectual Property Trial and Appeal Board (the “IPTAB”) and the Patent Court.

The Subject Patent relates to a hair bleaching method which comprises the step of adding maleic acid in order to prevent hair damages stemming from the use of alkaline hydrogen peroxide, among others.  A prior art reference discloses a hair dyeing formulation including maleic acid.  The key issue in determining the inventiveness of the Subject Patent was whether it was easy to apply the teachings of the prior art reference, which are directed to hair dyeing, to hair bleaching process of the Subject Patent.

Under the Korean Patent Act, any party (including a straw person) may file a patent cancellation petition (an ex parte proceeding) within six months from the date of patent publication for lacking novelty, inventiveness or violation of first to file rule with the IPTAB to revoke the grant of a patent.

In the present case, the IPTAB reviewed the patentability of the Subject Patent after institution and rendered its decision revoking the Subject Patent for lacking inventiveness in view of one of the new prior art references on the hair dyeing formulation, which was cited by the petitioner.  While the patentee appealed the decision to the Patent Court, since the cancellation action is an ex parte proceeding, a petitioner can only intervene to assist Korean Intellectual Property Office (“KIPO”), as the real parties in interest are the patentee and KIPO in the appeal proceedings.  Due to such a procedural limitation, it was strategically very important to assist KIPO to align it with the positions taken by the client (petitioner).

There were many pending cases worldwide including infringement and invalidation actions involving the family patents of the Subject Patent, which inevitably drew the Patent Court’s attention to the outcomes of those cases, such as the infringement action in the UK Supreme Court. Despite the unfavorable outcomes from other countries, Kim & Chang successfully defended and obtained a favorable decision in this case by effectively rebutting the patentee’s arguments which simply relied on the reasoning of the other jurisdictions’ decisions.

In doing so, we convinced the Patent Court panel by pointing out faulty reasoning of the other jurisdictions’ decisions and focusing on the technical similarities between the Subject Patent and the prior art.  Further, as an intervener to KIPO, we strategically assisted the KIPO solicitor by closely communicating with the solicitor, such as conveying the client’s positions to the KIPO solicitor so that both the client and the KIPO solicitor aligned their arguments to formulate the best possible arguments.