A care home where 19 residents died was riddled with "institutionalised abuse", a coroner has said.
Penelope Schofield has ruled neglect contributed to five of the deaths, at Orchid View in Copthorne, near Crawley.
The West Sussex coroner said the home, then run by Southern Cross, was "mismanaged and understaffed".
Ms Schofield has also criticised the Care Quality Commission (CQC), which gave the home a "good" rating in 2010, a year before it closed down.
A serious case review has now begun into the elderly residents' deaths.
At the final day of a five-week inquest into the deaths, which were all "unexplained", Mrs Schofield said the problems at the home were from the top down and started at an early stage, but nobody did anything to address them.
Orchid View has since reopened under a new name and new management.
Ms Schofield said it was "disgraceful" Southern Cross was allowed to run the home in the way it was, for about two years.
Referring to the CQC's rating of the home, she said: "I question how this could be the case and I question whether the inspection that did take place was fit for purpose.
"It's a heartbreaking case. We all have parents who will probably need care in the latter part of their lives."
Andrea Sutcliffe, the CQC's chief inspector of adult social care, said she had ordered a "root-and-branch review" of the organisation's actions in relation to Orchid View.
While summing up, Ms Schofield said she had found that medical documents for resident Jean Halfpenny, 77, were falsified and that she was given too much of the blood-thinning drug warfarin.
Home manager Meera Reed had earlier denied ordering staff to shred documents and filling in new forms to cover up the overdose.
Continuing, the coroner said that another resident was found naked and in pain with his catheter twisted, while a family member found staff eating toast and drinking tea with their feet up.
'Staff still working'
Whistleblower Lisa Martin, who first informed police of problems at Orchid View, said she felt she had no choice but to come forward.
Speaking outside the inquest, she said: "I had witnessed too much poor management and care to vulnerable adults.
"I couldn't live with the knowledge any longer and felt I had no choice but to tell the police."
She said she knew she had done the right thing morally, but said she had not worked for two years and the case had had a huge impact on her life.
Speaking of her former colleagues, she said: "They shouldn't be allowed to work in the industry."
During the inquest, the coroner also said it was a cause for concern that many people who worked at Orchid View were still working in the industry.
Ms Martin said when Mrs Halfpenny had to be admitted to hospital, Ms Reed looked at her forms and said: "We can't send her to hospital with those. They will shut us down."
She said other forms were filled out and she was asked not to disclose the shredding of the original documents to anyone.
She added that the final straw came when she was told by a nurse they had found 28 drug errors from just one night shift.
She called the police who arrived the next day.
Ms Schofield said that all 19 residents whose deaths were unexplained had suffered "sub-optimal" care.
She said they had all died of natural causes but the deaths of 86-year-old Enid Trodden, 85-year-olds Wilfred Gardner and John Holmes, and 77-year-olds Margaret Tucker and Jean Halfpenny "had been attributed to by neglect".
After the hearing, Mrs Halfpenny's daughter, Linzi Collings, said the horrific details that had emerged were beyond comprehension.
She said: "How the corporate failings of Southern Cross could create these events and how such terrible standards could go unnoticed by the authorities for so long has left us baffled."
She said her mother deserved to be treated with dignity and compassion, but Orchid View failed to provide her with even basic care, despite being paid a significant amount of money.
Lawyers for some families have called for a public inquiry to be set up, but the coroner said she would await the outcome of the serious case review first.
Ian Christian, of Irwin Mitchell solicitors, which represented seven families, said the situation at Orchid View raised questions about the quality of care provided across the industry.
He said before Southern Cross closed, it had owned 752 care homes.
"The evidence revealed in this inquest is deeply concerning as it shows signs of profits being put before the well-being of residents," he said.
Amanda Rogers, director of adult services for West Sussex County Council, said the inquest showed a shocking example of poor care, but such examples were "isolated" and the public should "remain confident" about the levels of care in West Sussex.
The CQC's Ms Sutcliffe said she was shocked at the descriptions of care at Orchid View in 2010 and 2011.
She said it was "completely unacceptable" and lessons needed to be learned.
She added that she would "personally oversee a root-and-branch review of our actions".
Ms Sutcliffe said she had already outlined changes to how care homes would inspected, monitored and regulated in the future.