The judgment below is reversed, and the case is remanded to the Patent Court.

The grounds of appeal are examined (to the extent of supplement in case of supplemental appellate briefs not timely filed).

1. In principle, the similarity of combined trademarks consisting of two or more letters or diagrams shall be determined on the basis of the overall appearance, name, and concept of their constituent parts.

However, in order to induce the conclusion of appropriate overall observation when there is an essential part, it is necessary to prepare for the similarity of trademarks with the essential part in order to induce the conclusion of appropriate observation.

In addition, whether the part of a trademark is essential or not shall be determined based on the elements such as whether the part is well-known or highly raised among ordinary consumers, and whether the part constitutes a high weight in the entire trademark. However, the determination should be made by comprehensively taking into account the degree of relative distinctiveness compared to other parts, its combination and degree, the relationship with the designated goods, and the transaction circumstances.

(See Supreme Court Decision 2015Hu1690 Decided February 9, 2017). 2. We examine in light of the aforementioned legal principles and records.

A. The trademark of this case’s international registration application (hereinafter “instant application trademark”) consists of “DDRONY” and “OPTPPS”, and if the trademark is referred to as the entire trademark, the trademark consists of relatively a relatively low level of drifies.

Priorly registered trademark 1 is composed of “” and is named as “observer” or “observer”.

B. The designated goods of the applied trademark of this case, “Catheters used in margaling” is installed in the pipe, such as rubber or metal agents, photographs inside the body of the human body and monitors and transmits them to monitor, and perform surgery or diagnosis outside the human body.