Probe Launched After Data Breach Impacts Thousands

An investigation is under way after a cyber security breach exposed the personal data of thousands of workers linked to a major trade union.

Data protection regulators in Guernsey, Jersey, the Isle of Man and the UK have opened inquiries into a cyber incident involving Prospect Custodian Trustees Ltd, which occurred in June 2025.

The Office of Data Protection Authority (ODPA) said Prospect represents more than 160,000 members across specialist sectors including science, engineering and technology. Around 3,000 people in the Bailiwick are believed to have been affected.

Prospect confirmed that personal information held by the organisation was compromised and issued an apology to members impacted by the breach. A spokesperson said those affected had been offered support, including access to credit monitoring services.

According to the ODPA, the data held by Prospect includes financial details as well as sensitive information such as trade union membership, ethnicity, sexual orientation, disability status and religious beliefs.

Regulators said their investigation will assess the scale of the data exposure, the risks posed to individuals and whether appropriate security measures were in place before the breach. They will also review how the organisation responded once the incident was discovered.

Prospect said it had reported the breach to the Information Commissioner’s Office in line with its legal obligations and had continued to cooperate with authorities.

“These types of incidents are becoming increasingly common,” the spokesperson said, urging members to make use of the support available to them.

Jersey Information Commissioner Paul Vane warned that cyber and phishing attacks are rising and are increasingly targeting organisations operating across multiple jurisdictions.

Guernsey Data Protection Commissioner Brent Homan said cooperation between regulators would help strengthen protections for citizens’ data rights across the British Isles.