Major Shareholding Report: Stake Edges Down to 32.95% on Insider Sales & Pledge Extension

Report on Mass Holding of Stocks, etc. (General) Version 6.0 Wonik IPS Co., Ltd. Report on Mass Holding of Stocks, etc. (General form: Reports under Article 147 of the Financial Investment Services and Capital Markets Act, in cases where the purpose is to influence management control) To: Financial Services Commission Reporting Obligation Trigger Date: May 11, 2026 To: Korea Exchange Report Preparation Reference Date: May 15, 2026 Reporter: Wonik Holdings Co., Ltd. [Summary Information] Issuing Company: Wonik IPS Co., Ltd. Relationship with Issuer: Largest Shareholder Report Type: Change / Modification Number and Ratio of Shares Held: - Previous Report: 16,189,983 shares (32.98%) - Current Report: 16,171,572 shares (32.95%) Number and Ratio of Shares Subject to Major Contracts: - Previous Report: 7,850,000 shares (15.99%) - Current Report: 7,850,000 shares (15.99%) Number and Ratio of Voting Rights: N/A Number and Ratio of Voting Rights Subject to Major Contracts: N/A Reasons for Filing: Extension and modification of terms of share-pledge loan agreement; change in special-related parties; on-market sales by special-related parties. The reporter confirms that, as of the reference date, the holdings of the reporter and special-related parties have been accurately prepared in accordance with relevant laws and disclosure guidelines, and there are no false statements or omissions of material facts. Part 1: Overview of Report 1. Information on Issuing Company - Company Name: Wonik IPS Co., Ltd. - Company Code: 240810 - Corporate Classification: KOSDAQ-listed company - Total Issued Voting Shares: 49,083,901 2. Information on Mass Holder A. Reporter (1) Reporter Overview - Report Type: Change / Modification (Joint filing) - Reporter Classification: Domestic Corporation - Nationality: Republic of Korea - Name: Wonik Holdings Co., Ltd. (WONIK HOLDINGS CO., LTD) - Address: Jinwi-myeon, Pyeongtaek-si, Gyeonggi-do - Business Registration Number: 133-81-27249 - Business: Semiconductor equipment manufacturing, etc. - Relationship with Issuer: Largest Shareholder - Contact: Wonik Holdings, Finance Management Team, Manager Kim Hyo-jeong, Phone 031-23******, Email ******kim@wonik.com (2) Specific Details on Reporter (Corporate) - Legal Form: Stock Company - Total Assets: KRW 1,969,723,238,243 - Total Liabilities: KRW 668,479,210,572 - Total Equity: KRW 1,301,244,027,671 - Capital Stock: KRW 38,618,990,500 - Representatives: CEO Cho Nam-sung, Jang Sung-dae - Decision-Making Bodies: General Meeting of Shareholders, Board of Directors - Largest Shareholder: Wonik Co., Ltd. - Largest Shareholder's Ownership: 30.00% (Note: Asset, liability, equity, and capital figures are based on consolidated financial statements as of end-2025.) Wonik Co., Ltd. (Largest shareholder of the reporter): - Legal Form: Stock Company - Total Assets: KRW 382,206,687,115 - Total Liabilities: KRW 95,590,639,527 - Total Equity: KRW 286,616,047,588 - Capital Stock: KRW 9,096,615,000 - Representative: CEO Jang Hong-sik - Largest Shareholder: Horizon LLC - Largest Shareholder's Ownership: 46.33% B. Special-Related Parties (1) Overview 1. Lee Hyun-deok — Domestic individual, Other, DOB 610307, Businessman, Address: Samseong-ro, Gangnam-gu, Seoul 2. Lim Chang-bin — Domestic individual, Executive (affiliate), DOB 610624, Businessman, Dogok-dong, Gangnam-gu, Seoul 3. Cho Nam-sung — Domestic individual, Executive (affiliate), DOB 590714, Businessman, Seongsu-dong, Seongdong-gu, Seoul 4. Park Sang-jun — Domestic individual, Affiliate Executive (unregistered), DOB 630108, Businessman, Dongtan-daero 24-gil, Hwaseong-si, Gyeonggi-do C. Collective Investment Operator: Not applicable 3. Number and Ratio of Shares Held - Previous Report (Dec 24, 2025): Wonik Holdings + 5 special-related parties — 16,189,983 shares (32.98%); total issued voting shares 49,083,901. - Current Report (May 15, 2026): Wonik Holdings + 4 special-related parties — 16,171,572 shares (32.95%). - Change: -18,411 shares (-0.03%). 4. Purpose of Holding: Influence over management A. Outline of holding purposes includes: (1) appointment/dismissal/suspension of directors and auditors; (2) amendment of articles related to corporate organs such as the Board; (3) change of capital; (4) dividend decisions; (5) M&A, division, and merger-by-division; (6) comprehensive share exchange/transfer; (7) transfer of all or significant part of the business; (8) disposal of all or material part of assets; (9) lease of all business, management delegation, or profit-sharing contracts; (10) corporate dissolution. B. The reporter and special-related parties exercise influence over the company as its largest shareholder with respect to items (1)–(10). No specific plans currently exist, but future actions will be determined in accordance with relevant laws and corporate purposes when management-related matters arise. 5. Reasons for Change/Modification - Change method: On-market sales by special-related parties; executive retirement. - Change reason: Change in special-related parties due to executive retirement and changes in their shareholdings. - Modification reason: Extension and modification of terms of share-pledge loan agreement. Part 2: Mass Holding Details 1. Holdings by Reporter and Special-Related Parties A. Holdings by Type of Securities - Wonik Holdings: 16,148,572 common shares (32.90%) - Lee Hyun-deok: 0 shares - Lim Chang-bin: 16,000 shares (0.03%) - Cho Nam-sung: 5,000 shares (0.01%) - Park Sang-jun: 2,000 shares (0.01%) No warrants, convertible bonds, BWs, exchangeable bonds, or DRs held. [Translation truncated]