Sooksun Popun-ngarm

Key Qualifications

Sooksun is a Partner at Chandler Mori Hamada and a core member of the firm’s Energy, Infrastructure, M&A and ESG practice, where he plays a leading role in advising on complex, high-value transactions across Southeast Asia.
He is regularly entrusted by multinational corporates, global private equity funds, and major Thai and Japanese strategic investors to lead transactions involving energy transition assets, regulated infrastructure, and cross-border acquisitions. Sooksun is recognised for his ability to combine technical legal expertise with commercial judgment, enabling clients to execute transactions in challenging and evolving regulatory environments.

Sooksun has led or coordinated numerous multi-jurisdictional transactions spanning Thailand, Laos, Vietnam, Cambodia, Myanmar, Bangladesh, and other regional markets, frequently acting as the central point of contact across local and Thai counsel teams. 
He currently serves as Counsel Leader of the AMCHAM Thailand ESG Committee, and is an active contributor to ESG thought leadership. His publications include the Thailand chapter of Slaughter and May’s ESG in APAC and contributions to Simpson Thacher & Bartlett LLP’s Sustainability and ESG Regulatory Update. He has also spoken at the Inter-Pacific Bar Association (IPBA) Conference on ESG developments in Asia.

Sooksun began his legal career in Bangkok and undertook regional secondments in Vientiane, Lao PDR, and Yangon, Myanmar, supporting clients on regional expansion initiatives. He is currently based in Bangkok.

Relevant Client Experience

Some Representative Transactions:

Energy and Infrastructure Transactions

Regulatory Engagement and Advisory

• State Enterprise Policy Office (SEPO): Collaborated with SEPO in organising and delivering capacity-building training seminars across five major cities in Thailand, focusing on PPP frameworks for government officers and private-sector investors.

   

• B.Grimm LNG: Advised B.Grimm LNG on regulatory and contractual aspects of Thailand’s Pool Gas Scheme, including the drafting and review of LNG-related agreements.

   

Energy and Infrastructure Transactions

• BlackRock–TiL / CK Hutchison Ports: Advised on Thai law aspects of the proposed acquisition of CK Hutchison’s port operations in Thailand.

   

• Levanta Renewables / Actis: 

  o    Lead counsel on the acquisition of a 139.4 MW portfolio of operating solar projects from Super Energy Corporation Plc.
  o    Lead counsel on the acquisition of a 91 MW operating solar portfolio from Thai Solar Renewable Co., Ltd. (a joint venture between Thai Solar Energy Plc. and Global Power Synergy Plc.).
  o    Lead counsel on the acquisition of a 94.33 MW operating solar project portfolio from Super Energy Corporation Plc.
   

• I Squared Capital: Lead counsel on the acquisition of an 18.91 MW portfolio of nine C&I solar PV projects from a joint venture between Power Systems & Solutions Co., Ltd. and Amarenco.

   

• Circulate Capital Ocean Fund I-B: Advised on its first investment in Thailand through a convertible bond issued by Union J. Plus Co., Ltd., representing the first foreign fund convertible bond issuance under the SEC’s exemption scheme.

   

• Dialog Group Berhad: Acted on the acquisition of 100% of the shares in a Thai petroleum company engaged in onshore exploration, production, and sales.

   

• Kai Heng Long Global Energy: Lead counsel on the acquisition of 100% of the shares in LAUGFS Gas, one of the largest LPG distributors in Bangladesh.

Corporate and M&A Transactions 

• PTT Tank Co., Ltd.: Advised on the establishment of a joint venture with Thai Oil Plc. for the long-term lease of core crude oil handling and storage facilities, with an aggregate transaction value of up to THB 37.4 billion.

   

• PTT Group: Represented Thai Oil Plc., PTT Plc., and IRPC Plc. in a joint investment in VISUP Co., Ltd., a deep-tech commercialisation platform established by VISTEC.

   

• ThaiNamthip: Lead adviser on a regional strategic investment involving the divestment and acquisition of Coca-Cola bottling operations across Thailand, Vietnam, Cambodia, and Laos.

   

• Mitsui Sumitomo Insurance Co., Ltd.: Lead counsel on the merger of MSIG Insurance (Lao) and Sokxay Insurance Company, the first private-sector merger transaction in the Lao PDR.

   

• Suntory Wellness / Lakeshore Capital: Lead counsel on the 100% acquisition of NBD Healthcare Co., Ltd., a Thai consumer healthcare products company.

   

• Clayton, Dubilier & Rice / OCS Group: Advised on Thai law aspects of the acquisition of OCS Group International, with a focus on PCS Security and Facilities Services Ltd. (Thailand).

   

• Cinven / Bayer AG: Advised Cinven on the Thai aspects of the acquisition of Bayer Environmental Science from Bayer AG.

Contributions

• Counsel Leader, AMCHAM Thailand ESG Committee

   

• Visiting Lecturer, Faculty of Law, Thammasat University (International Program): Delivered a full-semester course on Law on Investment.

   

• Contributor, ESG Publications:  

  o    Thailand chapter contributor to Slaughter and May – ESG in APAC.
  o    Contributor to Simpson Thacher & Bartlett LLP – Sustainability and ESG Regulatory Update.

   

• Speaker, Inter-Pacific Bar Association (IPBA) Conference, Panel speaker on ESG developments in Asia.
   

Background

• Kobe University (LL.M., 2019)
• University College London (LL.M. with Merit, 2013)
• Barrister at Law, Institute of Legal Education of Thai Bar Association (2011)
• Thammasat University (2nd  Class Honors, LL.B., 2009)

Qualifications

• Thai lawyer license, 2011

Memberships

• Member of permanent license to practice law, the Lawyers Council of Thailand, 2020
• Ordinary Member of the Thai Bar Association, 2011