The High Court has unanimously allowed an appeal against the decision of the NSW Court of Appeal in Goudappel v ADCO Constructions Pty Ltd. In 2010, Goudappel was injured in the course of employment with ADCO and suffered a whole person impairment of 6 per cent, and made a claim for compensation against ADCO. He later sought a lump sum compensation payment under s 66 of the Workers Compensation Act 1987 (NSW). That provisions was amended in 2012 to make lump sum compensation payments payable only to injured workers who suffered more than 10 per cent whole person permanent impairment, and was effective against claims made after 19 June 2012. The question before the NSWCA was whether the transitional provisions in the amending act meant the bar applied to claims for compensation generally, or only related to lump-sum payment claims specifically. The Court of Appeal held that the amendments do not apply to s 66 claims made before 19 June 2012 relating to an injury that results in permanent impairment, regardless of whether the claim was made under s 66 or s 67.The High Court held that the amendments did apply to claims made before 19 June 2012: the transitional regulation could not be interpreted so as to avoid its application to Goudappel’s claim. Examining the text, context and purpose of the regulation, the Court held that their purpose was ‘patently not beneficial’ to existing rights, and aimed to expand the regulation making power to allow regulations to affect those rights. The Court also rejected the argument that the transitional regulations were beyond the regulation-making powers in the Act.