On December 19, 2006, the Plaintiff entered into a contract between B (hereinafter “B”) and B (hereinafter “instant contract”) under which the Plaintiff shall supply the software products to B and pay the price for the said product to the Plaintiff within 60 days from the date of supply (hereinafter “instant contract”). The relevant contract for supply of the product (hereinafter “instant contract”) included the following contents:

The joint and several sureties of the joint and several sureties - The joint and several sureties of the “B (B)” shall, without objection, perform the joint and several sureties's liability for the debts currently incurred by the “B” and any obligations incurred in the future.

The duration of this contract shall be one year from the date of conclusion of the contract.

- Notwithstanding the above provisions, the term “A” or “B” is deemed to have been renewed under the same conditions unless it has expressed in writing to the other party one month prior to the expiration of the contract term.

- The renewal of the extended contract is also subject to the preceding paragraph.

The Defendant, without raising any objection or reservation on the same day, signed and sealed on the joint and several sureties column of the contract of this case, and jointly and severally guaranteed all obligations that B bears or will incur to the said contract.

The Plaintiff supplied software products to B from December 19, 2006 to August 31, 2015 under the instant contract and received part of the price. As a result, the remainder of August 31, 2015 was KRW 263,310,630.

On October 1, 2015, the Plaintiff sent to B and the Defendant a certificate of content that sought the payment of the unpaid amount respectively, and each of its content certification reached B and the Defendant respectively.

The above facts of recognition.