This paper examines how the adoption of artificial intelligence (AI) by firms in traditional and emerging sectors may affect competition. While much attention has focused on competition in AI infrastructure and foundation model development, the emphasis here is on how AI is used as an input into production, service delivery, logistics, and customer engagement. The paper is part of the OECD Horizontal Project on ‘Thriving with AI: Empowering Economies, Societies and Citizens’ and also contributes to a workstream of OECD “Competition and AI” papers that discuss steps in the AI value-chain, as well as various aspects of competition within the field of AI itself (see notably (OECD, 2024[2]; OECD, 2025[3]; OECD, 2025[4])).
AI adoption is heterogeneous across firms and sectors. Productivity effects also vary, with significant gains in professional services and manufacturing, but less in markets that largely rely on manual work and in-person services (Calvino, Reijerink and Samek, 2025[5]). The central question is whether using AI technologies helps lower barriers to entry and promote competition, or conversely may reinforce incumbency through control of data, compute, and ecosystems. AI can allow firms to automate, scale, personalise, and optimise outputs and services, supporting entry and innovation. At the same time, it may facilitate concentration of capability, vertical leveraging by dominant platforms, or new forms of anti-competitive behaviour, including algorithmic collusion.
The analysis does not aim to provide an exhaustive account of all sectors. Rather, the aim is to shed light on the factors and mechanics that support or hinder competition in the markets that adopt AI based tools. Given that issues specifically related to AI infrastructure will be addressed in a separate OECD paper (OECD, 2025[4]), this paper refers to them only insofar as they have direct implications for downstream competition.
As the topic is as yet under-researched and the sector is incredibly fast-moving, with daily breakthroughs, start-up launches or new uses reported in the media, many examples rely on press-reports or Internet research. Examples cited herein should be taken as illustrative as opposed to authoritative. Taken together, the aim is that these perspectives will contribute to a body of work to help readers better understand in which circumstances the use of AI is likely to be pro-competitive and hence, where regulators should seek to promote or protect its entry and use from vested interests or regulation; or conversely, to understand when the use of AI might be anti-competitive, and hence national competition authorities (NCAs) should be vigilant to protect competition across a wide range of downstream markets.