The judgment below is reversed, and the case is remanded to the Incheon District Court Panel Division.

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

1. A partnership is established if more than two members agree to carry on a joint business by making a mutual contribution (Article 703(1) of the Civil Act). Even if a juristic act was performed by an association acting as an agent for all members, if the juristic act was not indicated to be for commercial activities with respect to the partnership, the effect of such juristic act shall be effective against all the members of the partnership (see Supreme Court Decision 2008Da79340, Jan. 30, 2009). If an obligation of the partnership was to be borne by all the members of the partnership due to an act of commercial activities, it is reasonable to authorize joint and several liability of the union members by applying Article 57(1) of the Commercial Act.

(see, e.g., Supreme Court Decision 2014Da26521, Aug. 20, 2014). Meanwhile, an agent may also file a claim for performance, if the agent does not indicate that his/her act is for the principal in commercial transactions and the other party does not know that it is for the principal.

(Article 48 of the Commercial Act). 2. The court below acknowledged the fact that the party who entered into the interior contract with the Plaintiff is the husband C, and determined that the Defendant’s claim for the construction cost of this case against the Defendant is not reasonable on the ground that the Defendant cannot be deemed liable for payment of the construction cost under the circumstance that the Defendant completed business registration with respect to the burial of this case and operated together with husband C, even though it is not a party to the construction contract

3. However, the above determination by the court below is difficult to accept for the following reasons.

According to the records, the defendant completed business registration with the trade name "E" in Yangcheon-gu Seoul Metropolitan Government, and operated the store of this case with the defendant's husband C.