Thailand's stock market surges as Delta Electronics, a power-systems maker for AI data centers, becomes the country's first $100 billion（約16兆円） company.

What happened

Delta Electronics, which manufactures power-management systems for servers and data centers, has surged more than 80% this year and is now Thailand's largest listed company—worth more than the next four largest Thai stocks combined. The company now accounts for one-fifth of the Stock Exchange of Thailand Index, more than double its weighting in June 2025.

Why it matters

Thailand's stock market is outperforming Southeast Asian peers by more than 20% in 2026 through Wednesday, driven largely by Delta's rise. Investors are recognizing Thailand's role in supplying infrastructure for the global AI boom, offering a new lens on Thai equities beyond traditional sectors like tourism and banking. Delta's earnings have consistently beaten expectations every quarter over the past two years, suggesting the outperformance may continue.

What to watch

Delta is now Southeast Asia's second-most valuable company in the MSCI Asean Index, behind only DBS Group Holdings. However, Delta remains the only pure technology company among Thailand's five largest stocks; other major electronics producers in the country—Cal-Comp Electronics Thailand, KCE Electronics, and Hana Microelectronics—remain dwarfed by Delta, with market capitalizations exceeding $1 billion（約1600億円） only at times.