Keum Seok

Practice Areas

Antitrust & Competition

Merger Filings

Antitrust & Competition Compliance

Corporte Governance ∙ Conglomerates ∙ Holding Companies

Consumer Protection · Terms and Conditions

Product Liability

Class ∙ Group Actions

E-Commerce ∙ Labeling and Advertising (Dark Pattern, Greenwashing)

Mobility

Career

Keum Seok Oh is a partner at Yoon & Yang LLC, and his main practice are advising and handling fair trade & compliance and regulatory risk matters.

Mr. Oh served as a judge at the Seoul District Court Northern Branch, the Seoul District Court, and the Chuncheon District Court Sokcho Branch. Upon starting his career as a lawyer, Mr. Oh has represented a number of domestic and foreign companies on complex issues related to fair trade and compliance, including business combination (M&A), abuse of dominant market position, matters involving large-scale business groups, unfair trade practice, cartel, and violation of the subcontracting law. Notably, he has played a central role in fair trade cases involving global corporations such as Apple, HSBC, and Microsoft, as well as major domestic companies like Hyundai Mobis, Hyundai Rotem, LG Electronics, LG Uplus, Lotte Chemical, POSCO, Harim, Hoban Construction, and Maeil Dairies.

Professional Memberships

Admitted to bar, Korea (1989)

Certified Tax Accountant, Republic of Korea (2009)

Patent Attorney, Republic of Korea (2009)

Publications

[Books]

Theory and Practice related to the Act on Fair Transactions in Large Retail Business, Pakyoungsa (Co-author, 2012)

[Dissertations]

Case Commentary on Statute of Limitations for Disposition under the Fair Transactions in Subcontracting Act and the Monopoly Regulation and Fair Trade Act, Competition Journal No. 213, Korea Fair Competition Federation (Co-author, 2022)

Normative Control on Assessment of Damages Using Regression Analysis: Centering on the Damages Claim related to ATM Price Collusion, Competition Journal No. 203, Korea Fair Competition Federation (Co-author, 2020)

Review of Subcontract Payment Determined by a Unilaterally Low Price under the Fair Transactions in Subcontracting Act, Competition Journal No. 151, Korea Fair Competition Federation (2015)

Product Market Definition in Anti-Trust Cases Regarding Various Types of Electronic Commerce Intermediary Distributors, asialaw (Co-author, 2008)

Assessing the Impact of Resale Price Maintenance on Competition, asialaw (Co-author, 2007)

Recent Proposed Amendment to Korea’s Competition Laws, asialaw (Co-author, 2007)

Imputed Liability for Anti-trust Violations, asialaw (Co-author, 2007)

Requirements for Exercise of Set-off Right to Constitue Breach of the Good Faith Principle or Abuse of Set-off Right, Commentaries on Supreme Court Decisions No. 44, Supreme Court Library (2006)

Outcome and Remaining Challenges of the Pilot Implementation of Deliberation Preparation Procedures for Cases related to Violation of the Monopoly Regulation and Fair Trade Act, Competition Journal No. 124, Korea Fair Competition Federation (2006)

Claimant of National Tax Refund upon Determination of Overpayment Following Payment by a Tax Payment Guarantee Insurance Certificate, Commentaries on Supreme Court Decisions No. 40, Supreme Court Library (2002)

Comparative Review of Korean and U.S. Tax Law Provisions regardng the Treatment of Taxation Issues Arising from Divorce, Judicial Materials Vol. 93, Korea Association of Tax Law (2001)

Denial of Calculation of Wrongful Act under the Value-Added Tax Act, Study of Tax Law (1), Saegyeongsa (1995)

Study on Concept of Supply of Goods and Services and its Consideration under the Value-Added Tax Act, Seoul National University Master’s Thesis (1992)

Work Highlights

Represented Apple Inc. in an antitrust and fair trade law violation case related to Qualcomm's monopolistic practices.

Represented in a case concerning abuse of dominant trading position by Apple Korea.

Represented Microsoft in the case pertaining to abuse of market dominant position.

Represented Japansee steelmakers (i.e., Nippon Steel) in the case involving BHP Billiton’s acquisition of Rio Tinto shares.

Represented HSBC in a case involving unfair collusion in currency swap bidding.

Represented LG Uplus in a merger filing concerning the merger with CJ HelloVision.

Represented Hyundai AMCO in the case pertaining to illegal assistance to the company by Hyundai Motor Group.

Represented Samsung Welstory in the case pertaining to illegal assistance to the company by Samsung Electronics .

Represented Shinsegae Group in the case pertaining to the group’s illegal assitance to Chosun Hotel Bakery.

Represented Harim Group in the case pertaining to the group’s illegal assistance to Korea Thumb Vet Co., Ltd.

Represented Hoban Group in the case pertaining to the group’s illegal assitance to Hoban Industry.

Represented Hyundai Mobis in an administrative lawsuit before the Korea Fair Trade Commission regarding forced purchasing allegations and dealer push-out practices.

Represented Hyundai Rotem in the case regarding unfair collusive bidding for subway car contracts.

Represented Lotte Chemical in the merger filing for the acquisition of shares in SDI Chemical and Samsung Fine Chemicals (Korea, USA, Turkey, China).

Represented Hyundai HCNC in a merger filing for the acquisition of D’Live Seocho Broadcasting.

Represented Posco and Posco Chemtech in a case regarding unfair support practices.

Represented GS Engineering & Construction in the Fair Trade Commission investigation related to gas pipeline collusion.

Represented Asia Paper, Asia Papertech, and Gyeongsan Paper in regards to the Korea Fair Trade Commisssion’s investigation into bid rigging within the corrugated cardboard sector.

Represented Hotel Shilla in a case regarding unfair collusion among 8 duty-free shop operators.

Represented KB Insurance in a case regarding unfair collusion among 11 non-life insurers.

Represented in the prosecutor’s investigation regarding violations of consumer protection laws by Expedia in e-commerce.

Represented GS Retail in a case regarding violations of the Large-Scale Retail Business Act.

Represented Shinsegae Construction in a reported case related to unfair subcontracting practices.

Represented LG Chem in a reported case related to unfair subcontracting practices.

Represented the respondent, Seonjin FS, in a case regarding a distributor’s mediation request.

Represented Lotte Shopping in an administrative lawsuit regarding abuse of trading position.

Represented Harim in an administrative lawsuit regarding abuse of trading position.

Languages Spoken

Korean and English

Experience

2025-present Yoon & Yang LLC

2018-21 Member, Industry Reorganization Plan Deliberation Committee, Ministry of Trade, Industry and Energy

2018-20 Professor of Practical Training for Special Attorneys, Judicial Research and Training Institute

2012-13 Advisory Member, Committee on SME Regulatory Impact Assessment, Small and Medium Business Administration

2011-13 Advisory Member of Cartel Sub-committee, Competition Policy Advisory Committee, Korea Fair Trade Commission

2009-10 Steering Committee Member, Center for Competition Law, Law Research Institute, Seoul National University

2008-10 Professor of Practical Training for Civil Attorneys, Judicial Research and Training Institute

2008-09 Expert Member, Legislation Advancement T/F Team, Korea Fair Trade Commission

2006-07 Expert Member, Subcontracting Legal Framework Improvement T/F Team, Korea Fair Trade Commission

2005-06 Research Member, Research Council for Case Handling Procedure Improvement, Korea Fair Trade Commission

2004-07 Member, Information Disclosure Deliberation Committee, Secretariat of the National Election Commission

2004-06 Senior Advisor of Tax Law, National Tax Service

2004-25 Bae, Kim & Lee LLC

2002-04 Judicial Researcher, Supreme Court

1996-99 Judge, Chuncheon District Court Sokcho Branch

1994-96 Judge, Seoul District Court

1992-94 Judge, Seoul District Court Northern Branch

1989-92 Judge Advocate, Republic of Korea Army

Education

Awards