ANZ has been fined for failing to declare hundreds of millions of dollars in shares were bought by its underwriters during a capital raising venture.
The Federal Court on Friday ordered the bank to pay a penalty of $900,000 for breaching its obligation to transparently disclose where $2.5 billion in equity shares were issued during the 2015 raising event.
ANZ's underwriters stepped in to purchase leftover shares after the bank had sought to raise $2.5 billion in 2015 but did not reach that amount.
It did not disclose that information to the Australian Securities Exchange.
The bank was taken to court by the Australian Securities and Investments Commission for failing to act transparently in 2018.
In October, Justice Mark Moshinsky ruled ANZ contravened disclosure laws by failing to notify the ASX that ANZ shares had been acquired by its underwriters.
The amount in question totalled between $754 million and $790 million of the $2.5 billion of ANZ shares offered during the capital raising event.
Justice Moshinsky labelled the contravention very serious, saying a large penalty was required to achieve deterrence.
The ruling was a landmark case confirming that a significant take-up of shares by underwriters must be disclosed, ASIC deputy chair Karen Chester said.
"(It is) a clear and resolute message to ANZ and the market that this conduct was very serious," she said.
The maximum penalty for a single breach of continuous disclosure laws in 2015 was $1 million.
Tougher disclosure laws were implemented in 2019 enforcing a maximum penalty of up to $780 million, Ms Chester said.
"Listed entities should see today's penalty decision as a strong and purposeful warning to fully meet their continuous disclosure obligations.
"Continuous disclosure is key to maintaining market integrity."
The bank was also ordered to pay ASIC's court costs.
ANZ said it was considering Friday's decision together with the judgment delivered in October.