Bills of Exchange Act (Chapter 23): Primary legislation governing negotiable instruments including promissory notes in Singapore. Sets out the legal framework for creation, form, and enforcement of promissory notes.

Companies Act (Chapter 50): Governs corporate matters including authority requirements for intercompany transactions, directors' duties, and corporate execution requirements.

Singapore Contract Law: Application of English common law principles and general contract law principles that govern formation and enforcement of contracts in Singapore.

Stamp Duties Act (Chapter 312): Regulates stamp duty requirements and tax obligations for promissory notes and other instruments in Singapore.

Limitation Act (Chapter 163): Sets out the time limits within which legal actions can be brought to enforce the promissory note.

MAS Regulations: Monetary Authority of Singapore regulations that may apply if the transaction involves financial institutions.

Transfer Pricing Regulations: Rules governing pricing of transactions between related companies to ensure arm's length principles are maintained.

Foreign Exchange Control Regulations: Regulations governing cross-border transactions and currency controls if international companies are involved.

Corporate Authorization Requirements: Documentation and approval requirements for valid corporate authorization of the promissory note.

Interest Rate Regulations: Rules governing permissible interest rates and usury laws in Singapore for intercompany loans.

Tax Implications: Consideration of income tax, withholding tax, and other tax consequences of intercompany loans.