A Google-owned artificial intelligence company gained access to NHS blood test results without patients' knowledge.
According to the High Court case, the health records of more than 1.6 million people.
Google DeepMind said the lawsuit was "without merit" and vowed to fight it in court.
The claims about the blood test were made as part of a larger lawsuit brought against Google DeepMind by former Royal Free patient Andrew Prismall.
His claim questions whether the blood test results were also provided to Google DeepMind
Alleging that the US-owned business “failed to respond satisfactorily
Between 2015 and 2019, the medical records of 1.6 million people were handed over by Royal Free to Google DeepMind.
They used artificial intelligence algorithms to power a mobile app called Stream.
NHS administrators from the Royal Free have signed a data sharing agreement with Google DeepMind