ASIC declined to comment.

Usually, a government bond offering is executed by a group of banks, each of which manages a part of the process of selling the bonds to investors on behalf of the government. According to Bloomberg, ANZ has been the third-most used adviser of debt issuance in Australia, including state-level debt, this year.

ASIC’s investigation comes less than a decade after some lenders, including ANZ, were accused of rigging the bank bill swap rate – a benchmark interest rate. ANZ reached a settlement with ASIC, paying fines and admitting to attempted unconscionable conduct by some of its traders. In 2017, ANZ said it had changed the way it ran the markets business since 2015, including through more training of traders and new policies and systems.

Ahead of the federal budget to be delivered on Tuesday, global financial services group Nomura said it expected Australian government debt issuance to increase to between $80 billion and $95 billion in the 2024 to 2025 period, largely reflecting the maturity of the bonds.

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