Social care watchdog the Care Quality Commission (CQC) investigated Castlebeck after an undercover report showed residents with learning disabilities being slapped, doused in cold water and repeatedly taunted.
The CQC said it had serious concerns about three other Castlebeck services, while another seven did not not fully comply with essential standards of quality and safety.
CQC chief executive Cynthia Bower said: “We need to be clear: we have not found problems on the same scale as were found at Winterbourne View.
“However – we do have serious concerns at four locations in particular.
We have serious concerns at four locations in particular. The company needs to make root and branch improvements to its services and processes. Care Quality Commission Chief Executive Cynthia Bower
“In these cases we are taking action, although for legal reasons we cannot go into detail at this time. We will report fully later.”
She said the inspections uncovered a range of problems.
“The company needs to make root and branch improvements to its services and processes.
“Where we have had immediate concerns about people’s safety we have taken action. In the case of Winterbourne View we took action which led to its closure.
Following the report on BBC’s Panorama programme, 12 people who worked at the Winterbourne View care home were arrested.
Four other employees were suspended from Castlebeck’s Rose Villa care home in Bristol amid claims of misconduct.
Castlebeck chief executive Lee Reed said the company identified the areas for improvement when he took the job in January.
“We remain deeply sorry for all that happened at Winterbourne View and also apologise for any incidents where our services have in the past not met the high standards that we, those we support and their families, expect and deserve.
“There is no place within our organisation for services that fail to deliver high quality care.”