The UK’s Competition and Markets Authority (CMA) became the latest regulator to pressure Google over its open-display advertising technology, pressing the company for answers on how the set up works and adding to scrutiny by officials in the European Union (EU) and US.

A statement of objections was sent by the CMA to Google in which the authority expressed concerns the search giant may be hampering competition by abusing a dominant position by setting its own advertising exchange as a preferred option.

The CMA emphasised it is too soon to conclude any infringement of competition law had occurred, though interim executive director of enforcement Juliette Enser explained provisional findings indicate Google “is using its market power to hinder competition when it comes to the ads people see on websites”.

Enser noted many companies rely on advertising to offer digital content cheaply or for free, making it “important that publishers and advertisers” providing the information “get a fair deal when buying or selling digital advertising space”.

The CMA began looking into Google’s advertising technology in 2022 citing concerns the company was favouring its own services. It combined this work with a separate investigation into the search giant’s header bidding services “due to the interrelationship of the facts and conduct” between the probes.

Google is expected to provide responses to the CMA’s statement of objections between December this year and March 2025, with the regulator set to spend up to nine months considering those before deciding its next steps.

In 2023, the US Department of Justice initiated legal action against Google over its advertising practices and the EU came to the same conclusion as the CMA in a preliminary investigation.