Revisiting the Notion of Agreement in Australian Cartel Law in the Algorithm-Driven Economy

Pricing algorithms pose a conceptual and practical challenge for competition law. This article revisits the notion of agreement in Australian cartel law in the context of the algorithm-driven economy. It examines legal and academic approaches in the European Union, the US and the UK before applying these insights in the Australian context. The article focuses particularly on two kinds of pricing algorithms that pose challenges for Australian cartel law, namely parallel and signaling algorithms. We argue that parallel algorithms should be understood as falling within the concept of agreement for cartel law, although they present evidentiary challenges. Signaling algorithms, by contrast, constitute concerted practice under Australian law. They could also potentially fall within the cartel prohibition, but this would require empirical evidence of de facto collusion in the relevant market.