Adam Parore says he would be millions of dollars richer if he had not combined his assets with Auckland socialite Sally Ridge.
He made the concession from the witness box at the Auckland High Court today as his lengthy legal battle with his former fiance continues.
The court has heard that in 2007 Mr Parore and Ms Ridge split their family and commercial assets into two separate trusts - the Sally Ridge Family Trust and the Parore Family Trust.
"They wanted their family home insulated from any commercial trading liabilities," Mr Parore's lawyer Zane Kennedy said.
Mr Parore said from the witness stand that he and his trust would be in a significantly better position "to the tune of many millions of dollars" if they had retained their personal assets in separate trusts.
"This transaction was an absolute disaster for the Parore Family Trust and its beneficiaries," Mr Parore said.
Ms Ridge's trust is claiming up to $830,000 from the sale of a "palatial" property in Ponsonby's Arthur St, which the former couple sold after their 2010 separation for more than $6 million.
In court on Monday, Ms Ridge said following their split and the sale of the property Mr Parore walked away with $930,000 and 100 per cent of Small Business Accounting - the accountancy business she believed they co-owned - while she received $1.1 million.
She estimated she lost $900,000 on the property after a renovation project turned into a significant rebuild.
Ms Ridge is also claiming back pay and unpaid dividends from the accountancy business.
She said she hadn't received dividends from the business since September 2011 and wants a return to her relationship with the firm as it was in August 2011.
She was essentially a silent partner and received regular dividend payments, she said.
In the witness box yesterday she told the court "one day he [Mr Parore] woke up and decided he didn't want to pay me dividends anymore and tripled his salary".
"I was absolutely floored," Ms Ridge told the court. "I mean, who does that?"
Mr Parore refused to pay her dividends because she refused to contribute to the company's expenses or attend meetings, the court heard today.
Justice Murray Gilbert questioned why Mr Parore "turned off the tap" on dividend payments Ms Ridge was receiving from the business, removing her ability to service her mortgage.
Mr Parore's lawyer said she "didn't want to know" about debts the company needed to service, leaving Mr Parore in no position but to pay them.
"It got to the position where, despite what Ms Ridge said, he was in no position but to [cut her off]," Mr Kennedy said.
The business couldn't continue to pay Ms Ridge the dividends while continuing to service its previous debts, he said
"He tried on numerous occasions to sit down and have a meeting."
Whenever Mr Parore tried to discuss the arrangement with Ms Ridge, she wouldn't believe what she was being told, Mr Kennedy said.
"There is a very significant degree of distrust between the two of them."
The trial is set down for the rest of the week and will continue with Mr Parore in the witness box tomorrow.