Data linked to around 500,000 UK Biobank participants was reportedly listed for sale online. If you took part in UK Biobank, your data may have been involved.
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Overview
UK Biobank is one of the UK’s most significant health research projects, built on data from around 500,000 volunteers.
In April 2026, the government confirmed that data linked to UK Biobank participants had been found for sale on a Chinese e-commerce site. The data has since been removed, and there is currently no evidence it was purchased.
This was not a cyber-attack. A legitimate organisation is believed to have breached its agreement by making the data available for sale.
The data did not include direct identifiers like names or addresses. However, it was highly detailed, including health, lifestyle and demographic information.
While personal details where anonymised, the technology minister told MPs there was no guarantee individuals could not be identified from the data.
An investigation is now underway, with the Information Commissioner’s Office (ICO) making enquiries.
Even where data is anonymised, incidents like this can raise concerns about privacy, trust, and how personal information is handled over time.
Register your interest today and we will keep you informed if one of our regulated UK partner law firms is able to investigate potential legal action relating to the breach.
Biobank data breach – At a glance
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Latest updates on the Biobank data breach
April 2026
The government confirms UK Biobank data was listed for sale online. The ICO confirms it is making enquiries into the incident. Join the Claim starts raising awareness of the data breach.
We’ll provide more updates on the data breach as they occur.
Are you affected by the Biobank data breach?
Register to stay updated and we’ll let you know if a partner law firm takes this claim forward.
Frequently asked questions about the Biobank data breach
UK Biobank is a large-scale medical research project, using data from volunteers to study health conditions and improve treatments.
This wasn’t a cyber-attack. The data was accessed through a legitimate download by an approved research organisation. That organisation is believed to have then breached its agreement by making the data available for sale. The government has also said there is no evidence that any of the data was purchased, and the listings have now been removed.
The data did not include direct identifiers like names or addresses. However, it was still detailed, which is why concerns have been raised. The data accessed might include:
You may be affected if:
If you’re unsure, you may want to check any communications from UK Biobank or official updates.
The government has said there is no evidence the data was purchased before the listings were removed.
At this stage investigations are ongoing. It is not yet clear whether any legal action will follow. If a group action or formal claim is investigated by a regulated partner law firm, we’ll explain what it means and how to take part.
We are not a law firm. Our role is to keep people informed about potential group actions if one of our regulated UK partner law firms is able to take this claim forward.
By registering, you’ll stay up to date with any developments — from investigations to possible legal action.
No. Registering simply means you’ll receive updates. If a law firm later takes on the case, you’ll be given the option to learn more about the process and any potential costs before deciding whether to take part.
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