1. The defendant's appeal is dismissed.

2. The defendant supplementary intervenor shall bear the costs of appeal from among the costs of appeal.

1. Basic facts

A. The Plaintiff is an insurer who has entered into an automobile insurance contract with respect to a vehicle A (hereinafter “Plaintiff”), and the Defendant is the owner of C-si (hereinafter “Defendant”) driven by B and the user of the said B.

B. Around 23:05 on December 13, 2016, the Defendant’s vehicle is proceeding along the three lanes from among the three lanes in the direction of a wooden line in Seoul, the direction of right direction, etc. to change to the three lanes, while driving from the two lanes in the same direction, at the direction of a wooden line in Seoul, in order to change to the third lanes, at the vicinity of the steering point of the Seonam-dong Coast Highway. The lower portion of the Plaintiff’s assistant seat, which changed to the third line, was turned back to the third line, was turned back to the left side of the Defendant’s vehicle.

(hereinafter “instant accident”). C.

On December 26, 2016, the Plaintiff paid KRW 6,311,400 with the repair cost of the Plaintiff’s vehicle due to the instant accident.

[Ground of Recognition] Facts without dispute, Gap evidence 1 to 5, Eul evidence 1 to 4 (including each number), the purpose of the whole pleadings

2. Determination as to the cause of claim

A. The following circumstances are: (a) the occurrence of liability for damages and the overall purport of the arguments in the evidence revealed prior to the occurrence of the liability for damages; (b) the occurrence of an accident was caused in the course of changing the vehicle line of the Plaintiff’s vehicle; and (c) the road in which the accident occurred is the expressway; and (d) the degree of the occurrence of the accident is likely to cause the occurrence of the accident with the Defendant’s vehicle driving at the time of changing the vehicle line; (b) On the other hand, the Plaintiff’s vehicle operated direction direction direction, etc. for a considerable period of time when changing the vehicle line from the second line to the third line; and (c) the change of the vehicle line to the third line is not a small-scale change of the vehicle line to the third line to the degree that it is difficult to predict, but it is likely for the Defendant’s vehicle to prevent the accident.