1. The decision of the court of first instance, including the plaintiff's claim expanded by this court, is as follows.

Facts of recognition

A. The Plaintiff is an insurer who has concluded an automobile insurance contract with respect to A’s passenger vehicle (hereinafter “Plaintiff’s vehicle”), and the Defendant is a mutual aid business operator who has concluded an automobile mutual aid contract with respect to B’s bus (hereinafter “Defendant’s vehicle”).

B. On March 30, 2017, at around 18:20, the Plaintiff’s vehicle entered an expressway from the first two-lanes in the south East East East-dong, Incheon, the Southern East-dong, the Southern East-dong, along with the direction-setting intersection. The Defendant’s vehicle driven along the Plaintiff’s vehicle on the two-lanes, while driving the vehicle on the two-lanes, and changing the two-lanes from the two-lanes to one-lanes, the Defendant’s vehicle driven ahead of the right side of the Plaintiff’s vehicle to the left side of the Defendant vehicle while changing the two-lanes from the two-lanes to one-lane.

(hereinafter “instant accident”). C.

On August 17, 2017, the Plaintiff paid insurance money of KRW 334,710 as the repair cost of the Plaintiff’s vehicle, and paid KRW 3,027,860 as the insurance money from April 13, 2017 to May 25, 2017, for the medical expenses of C, the passenger of the Plaintiff’s vehicle, etc.

[Ground of recognition] Facts without dispute, Gap evidence Nos. 1 through 4, 9, Eul evidence Nos. 1 and 2 (including numbers; hereinafter the same shall apply) and the parties' assertion to the purport of the whole pleadings

A. The Plaintiff’s Defendant caused the instant accident by shocking the Plaintiff’s vehicle that was entering the expressway while moving ahead of the Plaintiff’s vehicle. As such, the instant accident occurred due to the total fault of the Defendant vehicle.

Therefore, the Defendant is obligated to pay the Plaintiff the indemnity amount of KRW 3,362,570 equivalent to the total amount of the insurance money paid by the Plaintiff in accordance with the insurer’s subrogation’s legal doctrine and delay damages.

B. While the instant accident attempted to change the lane from the access road to an expressway to the two-lane to the one-lane of the Plaintiff vehicle, the Plaintiff’s vehicle does not yield to the Defendant vehicle and is bound by the Defendant.