Oliver Peter Curtis has been found guilty over an insider trading scheme which netted more than $1 million, used to fund a lavish lifestyle in his early 20s.
The 30-year-old husband of well-known publicist Roxy Jacenko offered little reaction as the jury foreman handed down the verdict at the NSW Supreme Court on Thursday.
But Ms Jacenko, director of PR firm Sweaty Betty, appeared to wipe away tears in the moments that followed.
The defendant's father, mining magnate Nick Curtis, bowed his head briefly from the packed public gallery before hugging loved ones.
Curtis and Ms Jacenko, who had remained close during the high-profile trial, walked from the courthouse in opposite directions on Thursday.
Curtis remained at liberty throughout his trial and the two days of jury deliberations that followed, and was placed under tougher bail restrictions following the verdict.
He is expected to face sentencing proceedings on June 17.
The trial heard that Curtis made 45 trades for a profit of $1.433 million based on confidential information, given to him by former Orion Asset Management employee and high-school friend John Hartman, between May 2007 and June 2008.
Curtis also bought Hartman a brand new Mini Cooper and motorbike to the tune of $80,000 and transferred him $50,000.
The proceeds were also used to pay for a holiday with friends in Whistler and Las Vegas.
Hartman, who told brokers what to trade on behalf of Orion, would send Curtis messages directing him to buy or sell a particular number of Contracts for Difference (CFDs) on a particular company's stock at specific times.
On one occasion, Curtis traded more than 30,000 CFDs and earned $11,000, from the information on Orion, which managed $6 billion worth of stock at the time.
The trade was completed the day after he put $80,000 into a new CMC Markets trading account and two days after he bought Hartman a $99 Blackberry.
The court heard Curtis had known Hartman since the 1990s.
The former friends both grew up in Mosman and attended the prestigious St Ignatius College, Riverview.
Hartman has served a jail sentence for insider trading offences and received a discount for assisting Curtis' prosecution.
ASIC senior executive leader of markets enforcement Chris Savundra said he welcomed the verdict.
"It reinforces ASIC's commitment to pursue complex market misconducts such as these no matter how long they may take or how vigorously they are defended," he told reporters outside the court on Thursday.