Jasper Wells

Melbourne "rewards club" lottery billionaire Adrian Portelli has launched a defamation lawsuit against former SA minister Andrea Michaels over comments she made about a $3.5 million home prize draw.

The ASX 200 finishes the first session of the trading week with a fall of 1.45 per cent, continuing its downward trend this month. Meanwhile, uncertainty over the Iran war has sent Brent crude oil above $110 a barrel.

Some economists are forecasting price falls of up to 5 per cent as a result of measures to reduce intergenerational housing inequality.

Investors in stocks will be affected by changes to capital gains tax, but experts say the budget is still likely to see some investment move away from property and into shares.

"Rewards clubs" have exploded in Australia, claiming to have given away hundreds of millions in prizes, but they operate with almost no legal scrutiny. 

Supermarket giant Woolworths faced off with the consumer watchdog in court on Tuesday. The ASX 200 slipped into the red. Catch up on the day's events on the ABC News live markets blog.

RS Rewards claims to have given away more than $10 million worth of cars, houses and cash. But its licence has just been cancelled.

The oil price has surged again amid Iranian strikes on oil tankers and the fear there could be more attacks to come.

Gambling experts and US lawmakers have raised concerns about the ethics of online betting and whether insider information is helping profiteers cash in on war.

The technology sector is leading ASX's rebound after strong gains on Wall Street, and a court finds Star's former CEO and lawyer failed to exercise their powers and duties as directors. 

Iran's threats to attack vessels in one of the most important shipping passages will strain global supply of oil and gas, experts say — and Australia will not be immune from the fallout.