Businessman Sean Quinn said the reason he did not cut, and actually increased his investment in Anglo Irish Bank in 2007 was because he believed the bank was profitable.
“The logic in that was very clear. The share price had reduced by around 40pc, the profits had increased by 46 per cent in the year 2007. It was a phenomenal result.
"Where I come from those mathematics don't add up.”
The fact that accounts were signed by auditors, and assurances he got that the bank was in good shape, convinced him to boost the stake, he said.
“There were brokers left right and centre talking about Anglo being the best bank in the world. I could see no reason why you would see selling shares in Anglo would be a good idea. It turned out I was wrong”.
But he said by March 2008 "the kitty was empty" for the Quinn family, and agreed to a deal that would have involved selling a 9pc shareholding in the bank.
Mr Quinn is giving evidence in the fourth day of the trial of three former Anglo Irish Bank directors charged with multiple counts of allowing the bank to make loans to finance purchases of its own shares.
The three, Sean Fitzpatrick, Pat Whelan and Willie McAteer have pleaded not guilty to the charges.