The EU has launched an investigation into Google search over concerns the tech giant has been “demoting” commercial content from news media sites.

The bloc’s executive arm announced the move after monitoring found that certain content created with advertisers and sponsors was being given such a low priority by the US tech giant that it was effectively no longer visible in search results.

European Commission officials said this potentially unfair “loss of visibility and of revenue” to media owners may be as a result of an anti-spam policy Google operates.

Under the rules of the Digital Market Act (DMA), which governs competition in the tech sectors, Google must apply “fair, reasonable and non-discriminatory conditions of access to publishers websites on Google search”.

Commission officials said the investigation was not into the overall indexing of newspapers or their reporting on Google Search, just into commercial content provided by a third parties.

Media partnerships with businesses selling goods or services ranging from holidays to trainers were “normal commercial practice in the offline world” and they should also exist in a fair online marketplace such as Google, they said.

For example a newspaper may have teamed up with Nike to offer discounts, but there was evidence that under a Google search that sub-domain of the newspaper would be “demoted to a point that users will not be able to find it anymore” which then impacts the newspapers.

“We are concerned that Google’s policies do not allow news publishers to be treated in a fair, reasonable and non-discriminatory manner in its search results,” said Teresa Ribera executive vice-president for clean, just and competitive transition policies at the European Commission.

Officials will ask publishers to submit evidence of any impacts to its traffic and revenues as a result of suspected breaches of fair practices in the coming days, the Commission said.

Ribera added: “We will investigate to ensure that news publishers are not losing out on important revenues at a difficult time for the industry, and to ensure Google complies with the Digital Markets Act.

“Today we are taking action to ensure that digital gatekeepers do not unfairly restrict businesses that rely on them from promoting their own products and services.”

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The EU said it was compelled to take steps to protect traditional media which are now competing in marketplace online given the recent assertion by the European Commission president, Ursula von er Leyen, in her state of the union address that the “media at large is at risk” with the arrival of AI and widespread threats to media funding.

Officials stressed the investigation was a “normal non-compliance” probe and although fines of up to 20% of revenue could be imposed, that would only be a possibility of Google was found to be practising “systematic non compliance”.

The company said it is not looking at Google advertising services which are “not part of the organic search”.