Artificial intelligence (AI) technologies may be deployed across the advertising ecosystem, from optimising programmatic advertising and targeting, to content generation. Indeed, the digital marketing industry has utilised the technology for many years—almost all stakeholders in the digital advertising ecosystem, such as ad exchanges, networks, publishers, social media platforms and advertisers (or their media buying agencies on their behalf) have used AI to a lesser or greater extent to manage media buying budgets, real-time ad bidding and selling, reporting, placement/targeting at scale and the measurement of the success of ads. For more on the use of non-generative AI in digital advertising, refer to Further resources set out below. However, the recent surge in popularity for generative AI tools and technologies (referred to as ‘AI systems’ in this Practice Note) has revolutionised the industry and disrupted traditional monetisation models. With each change, new commercial and legal opportunities and risks arise. For example: • publishers of adverts, which typically rely on the number of impressions (sometimes referred to as ‘cost per mille’ or CPM) to generate revenue from ads served on their platforms,