1. The Plaintiff (Counterclaim Defendant) paid KRW 91,495,00 to the Defendant (Counterclaim Plaintiff) and its payment from May 1, 2014 to May 27, 2015.

A principal lawsuit and a counterclaim shall be deemed simultaneously.

1. Basic facts

A. On October 207, Korea publicly announced the instruction for proposal (RFP) for the implementation of the project to build an integrated network for national defense (hereinafter “instant national defense project”) by means of leased private investment (BTL) around October 2007, with a view to preparing for network-centered and future vision and improving poor telecommunication infrastructure.

B. The SKcom Co., Ltd. (hereinafter “SK”), KT, Military Mutual-Aid Association, and one telecom Co., Ltd. (hereinafter “SK”) participated in the process of selecting a project implementer by organizing a consortium to receive the instant defense project. The above four consortiums passed the prior qualification examination conducted around November 2007, but all failed to pass the equipment performance test (Benchmark Test, and BMT) conducted from December 2007 to January 208.

C. Accordingly, on or around March 8, 2008, Korea publicly announced the instruction for proposal for the defense project of this case, and around July 2008, after undergoing prior qualification examination and performance test of equipment, Korea selected SKS consortium as the priority negotiation object for the defense project of this case. On or around December 2008, it entered into a concession agreement for the implementation of the defense project of this case with the above SKS consortium, and on or around May 8, 2009, SKS consortium established Gangseo-gun C&C Co., Ltd. (hereinafter “Korean D&C”) for the purpose of promoting the defense project of this case.

On the other hand, in 2007, for the performance test of the above equipment of the SK consortium, the company's commencing telecom (hereinafter "ccom") is selected as a project implementer of the national defense project of this case, such as purchasing coconer, 750SR-12, and optical transmission equipment from the defendant company as the raw equipment for the performance test of the equipment.