Alphabet, Amazon, Apple, Meta Platforms (formerly Facebook) and Microsoft — often known as ‘Big Tech’ — are today five of the six largest companies in the United States (US) and world by market capitalisation. These firms have become systemically important to our economy and have come under increasing scrutiny from antitrust authorities in the European Union (EU), US, and other jurisdictions due to the considerable market power that they wield as gatekeepers to their business ecosystems. Policymakers, investors, and antitrust investigations, however, have all been hobbled by a disclosure regime that has not kept up with either the internet giants’ novel multisided digital platform business model or their relentless product diversification.