Watpac Constructions (NSW) Pty Limited v Charter Hall Funds Management Limited

The Court held that a payment claim under the SOP Act was valid where it comprised a tax invoice accompanied by copies of prior progress claims (Attachment A), because the construction work was sufficiently identifiable in context given the parties' knowledge of the contract history, consistent with the purposive and non-technical approach to s 13(2)(a) mandated by appellate authority. The contractually stipulated reference date was the date of submission of the tax invoice under cl 9.5(a), not the 25th day of each month when draft proposed progress claims were submitted under cl 9.2(a), because the contract expressly defined the reference date and the 25th-day submission was merely the first step in an assessment process. The estoppel and misleading or deceptive conduct defences both failed because Charter Hall's misunderstanding of the character of the cl 9.2(a) documents was self-induced and not attributable to any conduct or silence by Watpac, and a party to a commercial dispute has no obligation under the Australian Consumer Law to volunteer information to protect an equally sophisticated counterparty from the consequences of its own careless disregard of documents served upon it.