In the case, a married man, Mr. A, wrote a memorandum stating that he would give 100 million won to his affair partner, Ms. B, as a threat, and Ms. B filed a lawsuit for a gift based on this.

Hanbyol Law LLC Attorney Kim Jeon-soo explained that the legal issue of the memorandum is whether or not it was 'expressed under compulsion' and that Mr. A is responsible for proving the threat. He emphasized the importance of securing objective evidence, such as text messages and call recordings, and warned that without such evidence, the memorandum would likely be upheld.

According to Mr. Kim, in practice, it is possible to prove threats to cancel a memorandum of understanding, but it is important to focus on collecting evidence from the early stages, as the existence or absence of evidence is key to the decision.