Biggest Cyberattack in SK Telecom's History - Likely to Lead to Major Management Changes

• SK Telecom experienced the biggest cyberattack in its history in April which is likely to result in a major shakeup of its management team.

• We estimate SK Telecom could lose 1 million+ mobile service customers. Given its ARPU of 29,355 won per month, this would represent lost annual revenue of nearly 352 billion won.

• This massive cyberattack could cost SK Telecom more than 1 trillion won in a combination of lost revenue and additional commission/advertising necessary to attract new customers.

It takes 20 years to build a reputation and five minutes to ruin it." (Warren Buffett)