The convicted fraudster who oversaw the construction of the doomed CTV building allegedly patented a product similar to one designed by a New Zealand based mechanic shortly aftter living with the man.
Gerald Shirtcliff was the construction manager of the CTV building which collapsed in the Christchurch quake killing over 100 people.
Following revelations Shirtcliff allegedly lied about his engineering qualifications, a Nelson couple have come forward claiming he patented a similar product to one he saw while living with them.
Phil Stanley and Sue Lyons welcomed Shirtcliff into their family home in 2005 after he was released from prison.
"I went out to Rolleston Prison to a hearing and in front of a judge I stood up and I put his case to the judge that this poor old pensioner should not be wasting away in a prison, and that we were prepared to look after him," said Stanley.
Shirtcliff lived with the family for nearly two years at the same time Stanley was developing a patent for a dual fuel system.
It is now emerged Shirtcliff then applied to patent an allegedly similar product in Australia, months after he left his host's home in Nelson.
"In a very short time after returning to Australia he had supposedly developed and patented a dual fuel system very similar to what we were working on here and he had no previous knowledge of that," said Stanley.
The couple feel betrayed after letting Shirtcliff into their family.
"We've spent all our money on this project over the last ten years and we now have nothing, thanks to Gerald," said Lyons.
Shirtcliff was a crucial witness at the Royal Commission of Inquiry into the collapse of the CTV building in Christchurch following the devastating February 2011 earthquake.
He told the inquiry he was a qualified engineer but a recent investigation by The Press newspaper has cast doubt on that.
It claims that in 1970, Shirtcliff stole the identity of William Fisher, an engineer he once knew.
The paper alleged he adopted Fisher's birthday, birth place, and engineering degree as his own, in order to secure work and obtain a Masters degree.
He then worked in Australia under the false name.
In the 1980s he returned to New Zealand for a period of time, during which he supervised the construction of the CTV building.