(b) The case holding that in the case of paragraph (a), there is room for rejecting a third party's claim of property right against the principle of good faith or an abuse of right in the case where a dispute arises by searching the mother's inherited property on the family register;

B. The case holding that, in case where the establishment of a legal adoptive relationship cannot be acknowledged as mentioned in paragraph (a), in the case where there are circumstances such as the intention to establish a adoptive relationship between the mother and the person on the family register, other adoption requirements were met, and the mother on the family register had the intention to allow the person on the family register to inherit his/her own property at the time of the death, and a dispute arises due to the third party's assertion of his/her right to the inherited property by searching the mother's inherited property on the family register, there is room to dismiss the third party's claim of right to property by violating the principle of good faith or constituting an abuse of rights according to the specific circumstances.

1. According to the reasoning of the judgment below, the defendant is the father of the non-party 1 and the non-party 2 (the non-party 2's death on August 22, 1992) was born on April 20, 195 between the two children, but in fact, the non-party 2 was not born between the non-party 2 and the non-party 1, and his father is not known. However, the non-party 2 was born on the non-party 2's birth report at the time of birth report, upon request of the non-party 1's father's birth report, the non-party 2 was transferred to the non-party 2's mother and raised the defendant as the non-party 1's children on the non-party 2's birth report at the time of birth report, and the non-party 1 was not aware of the fact that the non-party 2 was born on the non-party 1's father's birth report at the time of birth, and thus, it was unnecessary for the defendant 1 to enter the above non-party 1.

2. We examine the second ground for appeal.

In addition, if the parties have an obvious intent to establish a adoptive parent relationship and the actual requirements of adoption are satisfied, if the report of birth of the father of a child instead of the report of adoption was made, it is interpreted that the adoption has the validity of adoption even if there were errors in the form of the adoption (see, e.g., Supreme Court en banc Decision 77Da492, Jul. 26, 1977). Furthermore, in such a case, as a child’s entry in the family register as the father of a child who is inconsistent with the truth has the effect of disclosing the parent-child relationship as a legal parent, barring any special circumstance such as where it is necessary to resolve the adoptive parent relationship due to the dissolution of adoption, a claim for confirmation of existence of paternity, which denies the existence of the legal parent-child relationship, shall not be allowed (see, e.g., Supreme Court Decision 85Meu86, Feb. 23, 198; 89Meu389

However, as in the case of this case, if a person entered as a mother on the family register did not report the birth of a person on the family register as a natural father, but had a male in an internal relationship with him to report the birth of a person other than a married person on the family register, even if the actual conditions of adoption were met between a mother on the family register and a person on the family register, it cannot be deemed that the adoptive parent relationship was formed between a mother on the family register and a person on the family register (see Supreme Court Decision 84Da458 delivered on November 27, 1984).

This is because, in such a case, if the actual requirements of adoption are not met between the father on the family register and the person on the family register, the report of birth of a person on the above family register is null and void, and thus, the entry on the family register on the report of birth should be cancelled by the decision confirming the existence of paternity between the two persons (see Supreme Court Decision 91Meu306 delivered on July 27, 1993). Thus, even if the actual requirements of adoption are met between the father on the family register and the person on the family register, it is impossible to recognize the adoptive relationship only between the mother on the family register and the person on the family register on the basis of the report of birth on the invalid father on the family register, and even if the Civil Code adopts the principle of common adoption between the father on the family register and the person on the family register, it is not permissible for those who are not the legal couple to jointly become the adoptive parent.

However, even in cases where the establishment of the legal adoptive relationship cannot be recognized, if there are circumstances such as the intention to establish the adoptive relationship between the mother on the family register and the person on the family register, and the other adoption was met, and the mother on the family register had the intention to have the person on the family register inherit his/her property at the time of his/her death, and the third party who is well aware of this intention has the intention to have the person on the family register inherit his/her property, and there is a dispute arising from the third party's assertion of his/her right to the inherited property by searching the mother's inherited property on the family register, there is room for rejecting the claim of the third party's property by violating the principle of good faith or constituting abuse of rights

Therefore, the court below's dismissal of the plaintiff's claim on the ground that the defendant and the non-party 2 constituted a legal adoptive parent relationship for the reasons stated in its reasoning is erroneous in the misapprehension of legal principles as to the establishment of adoptive parent relationship. Therefore, the ground for appeal pointing this out is with merit.

3. Accordingly, the judgment of the court below without examining the remaining grounds of appeal is reversed, and the case is remanded to the Seoul Family Court Panel Division, which is the court below. It is so decided as per Disposition by the assent of all participating Justices

Justices Lee Jae-soo (Presiding Justice)