Operation Roxburg, the multimillion-pound three-and-a-half-year police investigation into the Stepping Hill poisonings, was one of the biggest and most complex launched by Greater Manchester Police.
It involved 7,700 police 'actions', 659 witnesses, a 28,100-page prosecution file and 16,000 items of unused evidence material.
The arrest and charging of initial suspect nurse Rebecca Leighton in July 2011, until charges were dropped two months later, was thrown back in the face of the prosecution during the trial.
Chua's defence claimed the police had got it wrong then and were wrong now.
Outside court, Detective Superintendent Simon Barraclough said: "It's been a search for the truth and the jury has reached the right decision."
“Hidden in plain sight and using unsuspecting colleagues to carry out his sinister plan, Victorino Chua deliberately poisoned and murdered those who were under his care and those who were at their most vulnerable and most in need of help.
“The investigation and prosecution has been an enormous task involving the detailed analysis of thousands of pages of evidence relating to the hospital, its staff and patients, the forensic analysis of medical products and samples, expert medical evidence and many other aspects of what has been a very complex case."