Police alleged that SK co-ordinated an attack on Spamhaus in protest over its decision to add servers maintained by Cyberbunker to a spam blacklist.

BBC: Spamhaus hacking suspect 'had mobile attack van'

Among the largest underlying components of DEM, in trading today SK Telecom Co.

FORBES: DEM, SKM, KT, TEO: ETF Inflow Alert

Among the largest underlying components of DEM, in trading today KT Corp ( NYSE: KT) is off about 2.1%, SK Telecom Co.

FORBES: Notable ETF Inflow Detected - DEM, KT, SKM, IRS

Among the largest underlying components of DEM, in trading today KT Corp ( NYSE: KT) is up about 1.1%, SK Telecom Co.

FORBES: DEM, KT, SKM, IRS: ETF Inflow Alert

The companies whose networks shut down Wednesday afternoon use not just LG Uplus' services but also other services from SK Telecom Co.

WSJ: South Korea Banks, Media Report Possible Cyberattack