Companies need to give people more access to personal information held about them, according to UK data protection authority the Information Commissioner's Office.
More than a third of complaints the Information Commissioner's Office (ICO) received over the past financial year concerned "mishandled subject access requests", the ICO said in a statement on Friday.
"Organisations that handle personal information need to remember that customer records are not simply their property — the individuals who do business with them also have rights," said information commissioner Christopher Graham. "The result of mishandling requests is not simply a blip on customer service satisfaction levels, it can cause individuals a great deal of upset."
The financial sector had the most complaints in 2010/11 about letting people know information held about them, said the ICO. Health organisations and policing and justice bodies also attracted a number of data access complaints, the ICO added.