One of 10 investors who bought shares in Anglo Irish Bank with loans from the lender was told executives had legal advice for the deal, a court has heard.
Sean Reilly, a wealthy client of the bank for about 20 years, said he was called into its headquarters on St Stephen's Green, Dublin, on July 8 2008 and initially offered 60 million euro.
The builder, developer and investor was one of the so-called Maple 10 group lined up to buy Anglo shares to unwind a secret stock holding built up by former billionaire Sean Quinn.
Mr Reilly is the first of the select group of businessmen to give evidence at the fraud trial of three former Anglo executives over alleged illegal loans for share trades.
The bank's former chairman and one-time chief executive Sean FitzPatrick, 65, former chief risk officer Willie McAteer, 63, and former managing director of lending Pat Whelan, 51, deny 16 charges of providing unlawful loans for clients to buy shares in the bank.
Dublin Circuit Criminal Court heard Whelan contacted Mr Reilly and both he and former chief executive David Drumm, who is living in the US and not on trial, were in the Anglo offices when the 60 million euro was put on the table.
"They said they had legal opinion from MOP (law firm Matheson Ormsby Prentice) and that the financial regulator was aware of it, and the Central Bank, everyone was aware of it, and they wanted it done. That was it," Mr Reilly said.
The meeting lasted 30 minutes. Mr Reilly said he was only told the deal was to unwind a position and there was no mention of Mr Quinn.
The deal saw him take about 10 million shares - eight million of which he sold before the bank was nationalised in early 2009.
Mr Reilly said it did not look as though he could lose money and he was up seven million euro at one stage.
The court heard international bank Morgan Stanley would act for him in the deal.
Due to the share price continuing to collapse in July the loan was reduced to 45 million euro, documents showed.
Mr Reilly said he bought the shares on the condition he could sell them when he wanted but was asked by Mr Drumm not to flood the market.
Earlier, Sean Quinn Junior, the son of the bankrupt former billionaire, finished his evidence by disputing whether letters signed by him were dated correctly.
Mr Quinn Jr, 35, who lives in Dublin, also said he believed money lent to him and his sisters to buy ordinary shares from his father's secret stock holding was illegal.
"I think it's fair that we would be at one with the State and we would feel that the money that was lent was illegal," he said.
"It would be fair to say that it would be our view that the security obtained by the bank was obtained in a fraudulent and illegal manner and therefore we are not liable for those loans."
Several members of the Quinn family, including mother Patricia, were in court for day five of the trial.
Mr Quinn, of Ballyconnell, Co Cavan, said yesterday he lost 3.2 billion euro gambling on Anglo shares in 2007-2008.
The shareholding was built up by a Portuguese-registered company, Bazzely Ltd, which was part of the Quinn empire.
It used complex trading derivatives called contracts for difference (CFDs), which at the time did not have to be publicly divulged and essentially amounted to undeclared bets that the share price would increase.
The three accused pleaded not guilty to providing unlawful financial assistance to individuals in July 2008 for the purchase of shares in the bank, contrary to Section 60 of the Companies Act.
Whelan has also pleaded not guilty to a further seven charges of being privy to the fraudulent alteration of loan facility letters to seven individuals.
Lawyers for FitzPatrick and Whelan have said they accept the loans were made but they deny any illegality.
FitzPatrick, of Whitshed Road, Greystones, Co Wicklow; McAteer, of Auburn Villas, Rathgar, south Dublin; and Whelan, of Coast Road, Malahide, Co Dublin, are on bail.
The trial is expected to run until the end of May.