In New Zealand, the benchmark S&P/NZX 50 index rose as much as 0.4% to 12,776.60, hitting its highest level since Feb. 18 and rising for a fourth straight session.
Tuesday's figures from Australia and New Zealand Banking Group showed total job ads grew 9.2% in December from November, when they surged a revised 13.5%.
"We believe the combined business will have a stronger platform to offer enhanced digital capabilities for Aussie brokers and a superior experience for customers," CBA Chief Executive Officer Matt Comyn said in a statement.
The regulator has accused the investment banks of colluding over a A$2.5 billion ($1.8 billion) 2015 share issue to withhold unsold shares and keep the stock price from falling.