Ian David Shakespeare and Charles Ernest Frisby were both found guilty after a 15-week trial which started in January.
Detectives from the East Midlands Regional Fraud Unit began their investigation in the summer of 2009. It followed a complaint from a shareholder of Zoemack Ltd, Barlborough, that their investment funds had been misused by the directors of the company.
Zoemack Ltd, which was originally based in Chapeltown, South Yorkshire, entered administration in 2008 and at that time owed more than £7m to 90 private investors and more than £7m to four High Street banks.
Detectives took statements from more than 200 witnesses and gathered more than 500,000 pages of documentary evidence.
Detective Sergeant Andy Small, from the investigation team, said: “Investors and lenders involved with the company were duped into thinking that their money was being used for the sole purpose of purchasing and developing distressed properties. In reality, large amounts of their money was used to fund the lavish lifestyles of the two defendants, their families and their friends.”
“Many of the private investors were planning for their financial security as they entered their hard-earned retirement, but they were conned into re-mortgaging their family homes and cashing in their pension to invest in the scheme.”
Frisby, of Wales, near Sheffield, was found guilty of two counts of fraudulent trading for the time he was a director of Zoemack Ltd and Crestamax Ltd.
Shakespeare, of Rotherham, was found guilty of four counts of fraudulent trading for the time he was a director of Zoemack Ltd, Halewood Properties Ltd and Investrite Ltd
The jury deliberated for nine days before they reached their verdicts. Frisby and Shakespeare were due to be sentenced at 12noon on Thursday 21st May at Nottingham Crown Court.