Thailand’s Securities and Exchange Commission (SEC) has overhauled its approach to related-party transactions (RPTs) by issuing new rules that simplify approval processes while expanding oversight. Capital Market Supervisory Board Notification No. TorJor. 46/2568 will replace the longstanding Notification No. TorJor. 21/2551, which has governed RPT compliance for over a decade.

The new regulation takes effect on July 1, 2026. Any RPT matters approved by a company’s board of directors or approved for shareholders’ approval before that date remain subject to Notification No. TorJor. 21/2551.

The new RPT rules will introduce significant changes that market participants should carefully consider.

Consolidated Definitions

Under the previous framework, key definitions relevant to RPT compliance were dispersed across multiple sources, including SEC notifications, Stock Exchange of Thailand (SET) regulations, and provisions of the Securities and Exchange Act (before amendments).

The new regulation consolidates these definitions into a single notification. Concepts such as “related party” and “connected person,” as well as relevant transaction categories, are now more systematically organized and written in greater detail.

The SET has yet to issue corresponding regulations, which should include more detailed related disclosure requirements.

Unified Threshold and Mandatory Board Approval

The most significant change under the new regulation is the elimination of the multitiered approval framework based on transaction type. Instead of various categories, transactions are now classified as either (1) financial assistance provided to related persons, or (2) other RPTs in order to determine the level of corporate approvals and disclosures for each transaction size in these categories, but the concept remains the same.

Under the previous regulation, RPTs were divided into small, medium, and large transactions, with differing approval requirements. The new regulation effectively merges the small and medium categories. As a result, all RPTs must now be approved by the board of directors as a baseline requirement—a change from such approval not being required for small transactions under Notification No. TorJor. 21/2551.

Shareholder approval remains required if the transaction size reaches the prescribed threshold, which is largely unchanged from the previous regulation.

The minority veto mechanism, six-month progress reporting requirements, inclusion of updates in the Form 56-1 One Report, and parent-subsidiary dual approval exemption apply in the same manner as under the new material transaction rules issued by the SEC.

Expanded Aggregation Scope

While the past six-month transaction aggregation period remains unchanged, the new regulation expands the scope of persons whose transactions must be aggregated.

The previous regulation required companies to aggregate transactions with the same related party—including that party’s related persons and close relatives. The new regulation expands this requirement. Where the related party is a juristic person, companies must now also aggregate transactions involving the related party’s controlling persons and major shareholders, as well as any related persons and close relatives of those individuals.

Parent-Subsidiary Dual Approval Exemption

Similar to the new material transaction framework, where a subsidiary that is also a listed company fully complies with the RPT requirements, the parent listed company is not required to separately comply for the same transaction.

While this provision is intended to streamline compliance within corporate groups, it raises an important practical issue. The determination of “related persons” is company-specific and can differ from the perspective of each entity. For example, a person who qualifies as a related person of the parent may not be a related person of the subsidiary, and vice versa.

Without further clarification, this may cause potential gaps in shareholder protection, such as where approval by the subsidiary’s shareholders may not address conflicts that exist for different shareholders at the parent level, and where individuals who would be considered interested persons at the parent level may not be required to abstain from voting at the subsidiary level.

Companies and their advisors should consider whether additional safeguards or voluntary disclosures may be appropriate in situations where the related person relationship exists at the parent level but not at the subsidiary level. We anticipate that the SEC may provide further clarification or guidance on this matter.

Next Steps

Market participants should review related party identification processes, approval procedures, and transaction monitoring systems to align with the revised definitions, calculation methods, and aggregation requirements.

Given the scope of the amendments, further clarification from the SEC is expected. A formal guideline is likely to be issued, and both the SEC and the SET are expected to hold seminars to explain the new compliance framework in more detail. We will continue to monitor developments and provide updates as further clarification becomes available.