Key Stats
Founded: 1953 (as Sunkyong Textiles); 2007 (as SK Inc.)
Headquarters: Seoul, South Korea
Chairman & CEO: Chey Tae-won (since 1998)
Employees: Approximately 117,000 (SK Group)
Stock Symbol: KRX: 034730
SK Inc. (formerly SK Holdings) is the holding company of SK Group, one of South Korea’s largest chaebols. Headquartered in Seoul, the company manages investments in more than 175 subsidiaries spanning energy, chemicals, telecommunications, semiconductors, and biopharmaceuticals.
SK Group ranks as South Korea’s second-largest conglomerate by revenue, trailing only Samsung Group. In 2021, the conglomerate recorded combined revenues of $133 billion, with operations in 19 countries and more than 117,000 employees worldwide.
The company’s main subsidiaries include SK Telecom (South Korea’s largest wireless carrier), SK Hynix (the world’s second-largest memory chip manufacturer), SK Innovation (energy and chemicals), and SK Biopharmaceuticals. SK Inc. focuses its strategic investments on four areas: high-tech materials, bioscience, green business, and digital technology.
SK Inc. History
1953
Sunkyong Textiles Founded
Chey Jong-gun purchases the war-damaged Sunkyong Textile plant from the Korean government after the Korean War. The company rebuilds operations with salvaged looms and begins producing textiles in Suwon.
1958
First Polyester Fiber in Korea
Sunkyong manufactures Korea’s first polyester fiber, establishing the company as a pioneer in the country’s textile industry.
1973
Vertical Integration Begins
Chey Jong-hyon takes over leadership after his brother’s death. He establishes Sunkyong Oil, launching the “From Petroleum to Fibers” vertical integration strategy.
1980
Korea Oil Corporation Acquired
Sunkyong acquires a 50% stake and management control of Korea Oil Corporation (later renamed Yukong, then SK Energy), becoming a major player in the petroleum industry.
1994
Entry into Telecommunications
Sunkyong acquires a 23% stake in Korea Mobile Telecommunication Service, entering the wireless communications market. The company later merges this with its Daehan Telecom subsidiary to form SK Telecom.
1998
Rebranding to SK Group
Sunkyong Group is rebranded as SK Group. Chairman Chey Jong-hyon passes away, and his son Chey Tae-won assumes leadership at age 38.
2007
Holding Company Structure
SK Corporation is reorganized into a holding company (SK Holdings, now SK Inc.) and an operating company (SK Energy), creating the modern corporate structure.
2012
SK Hynix Acquisition
SK Holdings acquires Hynix Semiconductor, transforming it into SK Hynix. The deal marks a watershed moment for the group’s expansion into the semiconductor industry.
SK Inc. Founders
Chey Jong-gun
Founded Sunkyong Textiles in 1953 by acquiring a war-damaged textile plant from the Korean government. Chey rebuilt the factory with salvaged looms and established the company’s initial textile operations. He led the company until his death in 1973 at age 47, when leadership passed to his brother.
Chey Jong-hyon
Younger brother of the founder, Chey Jong-hyon earned degrees from the University of Wisconsin and University of Chicago before joining Sunkyong in 1962. He took over leadership in 1973 and transformed the textile company into a diversified conglomerate, expanding into oil, chemicals, and telecommunications. He led the company until his death in 1998.
SK Inc. Acquisitions
SK Group’s growth has been driven by strategic acquisitions that expanded its presence beyond textiles into energy, telecommunications, and semiconductors. The company’s acquisition strategy has focused on vertical integration and entry into high-growth industries.
The 1980 acquisition of Korea Oil Corporation (later Yukong) marked SK’s transformation from a textile company to an energy conglomerate. This deal, valued at the time as one of the largest in Korean corporate history, gave SK control of major refinery operations and positioned the company to dominate the domestic petroleum market.
SK’s 1994 acquisition of Korea Mobile Telecommunication Service and subsequent formation of SK Telecom created South Korea’s dominant wireless carrier. SK Telecom launched the world’s first commercial CDMA service in 1996 and the first commercial 3G EV-DO service in 2002.
The 2012 acquisition of Hynix Semiconductor represented SK’s largest strategic move. The deal transformed SK into a semiconductor powerhouse and gave the group control of the world’s second-largest memory chip manufacturer. SK Hynix has since become the group’s most valuable subsidiary and a global leader in high-bandwidth memory (HBM) chips for AI applications.
More recently, SK has made substantial investments in EV batteries, green hydrogen, and biopharmaceuticals. In 2021, SK invested $1.6 billion in Plug Power for hydrogen fuel cells. SK On, the group’s battery subsidiary, has built manufacturing plants in the United States through a joint venture with Ford Motor Company.
SK Inc. Revenue
SK Inc. (consolidated with subsidiaries) reported revenue of approximately $90 billion in 2024. The company’s revenue growth has been driven by its diversified portfolio of energy, telecommunications, and semiconductor businesses.
SK Inc. Marketcap
SK Inc. has a market capitalization of approximately $15.6 billion as of February 2026. The company’s valuation reflects its position as a holding company with stakes in major subsidiaries across multiple industries.
SK Inc. Competitors
SK Group competes against other major South Korean chaebols as well as global companies in specific industry segments. The conglomerate’s diversified business structure means it faces different competitors across its telecommunications, semiconductor, and energy divisions.
| Company | Headquarters | Primary Business |
|---|---|---|
| Samsung Group | South Korea | Electronics, semiconductors, shipbuilding |
| Hyundai Motor Group | South Korea | Automobiles, steel, construction |
| LG Corporation | South Korea | Electronics, chemicals, telecommunications |
| Lotte Corporation | South Korea | Retail, food, hospitality, chemicals |
| Micron Technology | United States | Memory semiconductors |
| KT Corporation | South Korea | Telecommunications |
| S-Oil Corporation | South Korea | Petroleum refining |
| GS Group | South Korea | Energy, retail, construction |
| Hanwha Group | South Korea | Chemicals, aerospace, finance |
| CATL | China | EV batteries |
FAQs
What does SK Inc. do?
SK Inc. is the holding company of SK Group, managing investments in subsidiaries across telecommunications, semiconductors, energy, chemicals, and biopharmaceuticals. It controls companies like SK Telecom, SK Hynix, and SK Innovation.
Who owns SK Group?
SK Group is controlled by the Chey family through SK Inc. Chairman Chey Tae-won, grandson of the founder, has led the conglomerate since 1998 and holds significant stakes through direct ownership and affiliated holdings.
Is SK a chaebol?
Yes, SK Group is South Korea’s second-largest chaebol (family-owned conglomerate) by revenue. The group comprises 186 subsidiaries and affiliates spanning multiple industries including energy, semiconductors, and telecommunications.
What is SK Hynix known for?
SK Hynix is the world’s second-largest memory semiconductor manufacturer. The company is a leading producer of DRAM and NAND flash memory chips, and has become a major supplier of high-bandwidth memory (HBM) for AI applications.
When was SK Group founded?
SK Group traces its origins to 1953 when Chey Jong-gun acquired Sunkyong Textiles. The company was rebranded from Sunkyong Group to SK Group in 1998, and the holding company structure (SK Inc.) was established in 2007.