Morrison’s was found liable for the actions of a former member of staff, stole the data of thousands of employees and put it online.
Employee brought a claim against the company, according to employee Andrew Skelton the data stolen, including wage and Bank data, of the almost 100,000 employees.
The High Court’s verdict now allows the affected, compensation for the “upset and distress” caused.
The case is the first leak class action in the United Kingdom.
Morrisons said it believed it should not have been held responsible and would appeal against the decision.
The case follows a security breach in 2014, when Skelton, a senior internal auditor at the dealer the Bradford headquarters, licked, wage and salary data for the employees.
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He published the information – including names, addresses, Bank accounts and salaries online and sent them to Newspapers.
Skelton’s motive, apparently holding a grudge over an incident in which he was accused of handling the so-called legal highs at work.
West Yorkshire Police
He was imprisoned for eight years in 2015, after he was found guilty in Bradford Crown Court of fraud, is the securing of unauthorised access to computer material, and the disclosure of personal data.
Prosecutors said that the data theft meant 5,518 former and current employees were exposed to the risk of identity theft and possible financial loss and the company was responsible for breaches of privacy, confidence and data protection laws.
At the High Court hearing, sitting in Leeds, the judge, Mr justice Langstaff, decided that Morrison’s was vicariously liable, adding that the primary liability was not established.’Of Great Importance’
Anya Proops, QC for Morrisons, said Skelton had already caused serious damages to the company, and had it emerged more than Â£2m in costs, in response to the abuse.
She argues that the extent to which an employer shall be liable to could was for the criminal misuse of third party data by an employee of the “enormous importance” for individuals, companies and organizations.
After the judgment, Nick McAleenan of JMW Solicitors, representing the plaintiffs, said the leak had caused “significant worry, stress and inconvenience”.
He said: “This private information to my clients. You are to do Morrisons checkout staff, shelf stackers, factory workers, ordinary people in their work.
“We welcome the judgment and believe that there is a principle decision, as the first leak class action in the United Kingdom.”
Any further negotiation about the amounts will not take place until the company has closed the complaint.