Britain’s National Health Service (NHS) allowed secretive US technology company Palantir Technologies access to sensitive personal data of patients, employees and members of the public under a deal to help it cope with the Covid-19 outbreak.

The data ranged from contact information to details of gender, race and work, and physical and mental health conditions, according to a copy of the contract struck in March and published on Friday by politics website OpenDemocracy and law firm Foxglove. It also included details of political and religious affiliation and past criminal offences.

Faculty, a London-based artificial intelligence (AI) firm, is also working on the NHS’s coronavirus response and secured access to sensitive data.

Under the Palantir agreement, names or other personal identifiers are replaced with a pseudonym or aggregated before being shared with the companies. Sensitive personal information such as race and political affiliation would only be provided to Palantir where such access is “lawful and critical in the performance of its obligations”, according to the contract terms.

A representative for Palantir did not immediately respond to requests for comment.

Faculty spokeswoman Holly Searle said the company had asked for its contract to be amended to make clear it will derive no commercial benefit from any software developed during the course of the project “and that the use of the intellectual property is under the sole control of the NHS”.

“This project is helping us tackle coronavirus, by helping track information about where demand is rising and where critical equipment needs to be deployed, and strict data protection rules apply to everyone involved in helping in this important task,” a representative from NHSX, a government unit that sets national policy for NHS technology and data, said in an emailed statement.

“The companies involved do not control the data and are not permitted to use or share it for their own purposes, with any intellectual property owned by the NHS and contracts strengthened following review as appropriate.”

Palantir, co-founded by billionaire venture capitalist Peter Thiel, makes software that mines troves of personal data and looks for patterns.

The company got its start working for the US Central Intelligence Agency and the Pentagon, interpreting battlefield intelligence in Afghanistan and Iraq as well as helping to flag suspicious behaviour patterns to stop terrorist attacks at home.

It moved on to banks, helping bosses watch for suspicious behaviour or signs that employees were disgruntled. The FBI and police have used Palantir in criminal investigations. Its work has drawn scrutiny from privacy advocates in the US.

Technology giants Microsoft Corp, Amazon Web Services and Google are also involved in the deal with the NHS. The companies are tasked with building a data platform to help understand how Covid-19 is spreading across the country and the capacity of its health care system to deal with it. The project was envisioned as a way to assess occupancy levels at hospitals, capacity in emergency rooms and statistics on how long patients are being kept in hospital.

The NHS is using Palantir’s Foundry product, which is targeted at businesses and government institutions. The health body has previously disclosed dozens of data sets that will go into a Palantir data store, ranging from ventilator orders and epidemiological data to details such as the categories of people working in adult social care.

The company must destroy or return the data to the NHS at the end of its contract, and only certain members of the Palantir team who have been authorised by the NHS will get access to it, according to a health service impact assessment that was also published Friday.

Faculty is run by Marc Warner, whose brother Ben Warner, a data scientist, worked with the Vote Leave Brexit campaign and has attended meetings of a scientific advisory group to guide the government on its coronavirus response strategy, The Guardian newspaper has reported.

Faculty’s contract will use data from the health care system to model the spread of Covid-19 and its impact on resources. The start-up will help design an NHS AI lab, develop frameworks for the adoption of AI technology, improve data analytics and help to create a national chest X-ray database.

The company agreed not to store any data except those it needs to fulfil the contract, and sensitive information will also be modified to remove identifiers.