Singapore Contract Act 1872: Primary legislation governing contract formation, validity, and enforcement in Singapore, including principles for contract modification
Electronic Transactions Act: Legislation governing electronic signatures and digital contracts, relevant if the addendum will be executed electronically
Sale of Goods Act: Relevant if the original agreement involves commercial transactions or sale of goods
Employment Act: Must be considered if the original agreement and addendum relate to employment matters
Companies Act: Relevant for corporate matters and when parties are corporate entities
Competition Act: Must be considered if the agreement involves business competition or market practices
Civil Law Act: Contains provisions regarding execution of documents and contractual formalities
Stamp Duties Act: Governs stamping requirements for certain types of agreements and their modifications
Variation of Contracts: Common law principles governing how existing contracts can be modified through addenda
Doctrine of Consideration: Legal principle requiring new consideration for contract modifications under common law
Legal Capacity Requirements: Rules governing who can legally enter into or modify contracts
Amendment Procedures: Any specific amendment procedures that might be specified in the original agreement
