The Siam Cement Public Company Limited (SET: SCC), through its wholly owned subsidiary SCG Chemicals (SCGC), and PTT Global Chemical Public Company Limited (SET: PTTGC) have agreed on key terms for a proposed Thai petrochemical joint venture combining businesses valued at THB186.514 billion. The transaction would give PTTGC a 56% controlling stake and SCGC 44%, with the companies projecting recurring annual synergy and integration benefits of THB5.1–6.8 billion or more once fully realized.
In disclosures to the Stock Exchange of Thailand on October 28, 2026, SCC confirmed agreement on the ownership split, transaction structure and estimated synergies. PTTGC’s board separately resolved to submit the business combination to shareholders for approval at an extraordinary general meeting on December 3, 2026.
The parties agreed to value PTTGC’s contributing businesses at THB104.448 billion and SCGC’s at THB82.066 billion, following negotiations using discounted cash flow valuations.
PTTGC will establish a wholly owned subsidiary, GC SPV, to receive its Thai olefins and polyolefins operations, associated infrastructure and liabilities, alongside its investments in HMC Polymers and GC Marketing Solutions.
SCGC will reorganize its participating businesses under Thai Polyethylene (TPE). GC SPV will then merge with TPE, remaining as the surviving company and issuing shares to SCGC. TPE will cease to exist as a separate legal entity.
The merger consideration will be entirely share-based, with no external funding required to finance it. However, either party may need to make additional capital injections if pre-merger working capital differs from agreed levels.
The proposed venture would combine PTTGC’s upstream production, feedstock access and refinery-linked infrastructure with SCGC’s downstream manufacturing, technology and higher-value product capabilities.
Expected benefits include better feedstock allocation, coordinated production and maintenance, procurement savings, and more efficient logistics and marketing. PTTGC said the anticipated synergies would primarily use existing assets without requiring additional capital expenditure.
The estimates remain subject to execution and market conditions, have not been independently audited or reviewed, and do not constitute a profit forecast.
SCGC’s contribution includes Thai crackers and polyethylene and polypropylene facilities, together with investments in Siam Polyethylene, Siam Synthetic Latex, Thai MMA and Bangkok Synthetics. PTTGC’s contribution includes its Thai crackers and polyethylene plants, its 41.4% interest in HMC Polymers and its wholly owned GC Marketing Solutions business.
SCGC’s Long Son Petrochemicals project in Vietnam and its vinyl-chain businesses remain outside the proposed combination.
PTTGC will retain control and fully consolidate the venture’s financial statements. It will nominate four of seven directors and the chief executive, while SCGC will nominate three directors and the deputy chief executive.
SCC, by contrast, will account for the investment as an associate using the equity method. The participating Thai chemicals businesses will consequently be removed from line-by-line consolidation in SCC’s balance sheet and income statement.
The venture targets an annual dividend payout of at least 60% of consolidated net profit, subject to applicable reserve requirements and the policy’s provisions for investment, working capital and operating needs.
PTTGC has set November 11, 2026, as the record date for meeting eligibility. Approval requires at least three-quarters of eligible votes cast by attending shareholders, excluding interested shareholders. Asia Plus Advisory has been appointed independent financial adviser.
Completion also requires SCGC shareholder approval, competition clearance, other regulatory permissions and relevant third-party consents.
SCC’s timetable targets competition approval and completion of other conditions in the first half of 2027, followed by closing and formation of the venture in the second half. The companies identified industry volatility, integration challenges and approval delays as risks to the timetable and expected benefits.
