In his closing address to a Supreme Court jury, defence barrister Joshua Wilson, QC, said Dr Mervyn Jacobson was a person of good character who had no need to set up a scheme to prop up the share price of his company, Genetic Technologies.

Dr Jacobson, 72, of Brighton, has denied claims by the Crown that he was a "fraudster".

"He honestly believes that he did nothing wrong in this case," Mr Wilson said.

He claimed the conspiracy theory allegedly involving Dr Jacobson could have come straight from a Hollywood movie.

"His personal wealth was in the vicinity of $100 million ... is there a burning need for a man of such substance to engage in the criminality that our friends (the Crown) contend, given that he had assets all over the world?" Mr Wilson said.

The defence barrister pointed to how Dr Mervyn Cass, a lifelong friend of Dr Jacobson's, had given evidence during the trial of Dr Jacobson's good standing in the community.

"You might remember him telling you that Dr Jacobson received commendations for his work from organisations worldwide, the United Kingdom, in the USA and in Africa.

"You might recall Dr Cass telling you that Dr Jacobson was a devoted family man, that he was generous to his children and that Dr Jacobson was the patron of the arts and actively involved in animal welfare matters."

Mr Wilson said Dr Cass spoke glowingly about Dr Jacobson despite having lost money investing in Genetic Technologies shares, which were now worth about one-and-a-half cents each.

"Instead of him slagging off at Dr Jacobson, saying unkind things, accusing him of being the cause of the fact that his (GeneticTechnologies) shares are next to worthless, he didn't say that at all.

"We want you to believe that Dr Jacobson is, as Dr Cass says, a man of good character. Very important, ladies and gentlemen."

Dr Jacobson, 72, of Brighton, has pleaded not guilty to 35 charges of conspiracy to manipulate the market and fund transactions to create an artificial share price between May and November 2006.

Crown prosecutor Jeremy Rapke, QC, has described the case as one of price-fixing.

Dr Jacobson had been involved in research and other activities involving human genetic material before Genetic Technologies invented a method to obtain valuable information located within what is called the non-coding DNA of all species.

Shares in Genetic Technologies were listed on the Australian Stock Exchange (ASX) and Dr Jacobson controlled more than 40 per cent of the company's shares, totalling over 150 million shares.

The Crown case alleged Dr Jacobson's daughter, Tamara, and her second husband, Geoffrey Newing, from Toorak, acted illegally and were heavily involved with Dr Jacobson in manipulating the price of Genetic Technologies shares on the ASX.

Mr Rapke said much of Dr Jacobson's wealth was tied up in the company and his financial stability was dependent on the company's success and its share price.

So when the share price began to fall and Dr Jacobson started receiving margin calls on a $11.4 million loan with Opes Prime, Mr Rapke said Dr Jacobson gave more than $1.55 million to his daughter.

The prosecutor said Tamara, her husband and two stock brokers then used the money to buy Genetic Technologies shares on the ASX to maintain the price at an artificially high level.

Dr Jacobson has admitted giving Tamara large sums of money but claimed the cash was a gift.

The trial, before Justice Stephen Kaye, continues.