Melbourne Cup 2025: Macquarie’s ‘PunterGPT’ AI has another try at picking winner after 2024 blunder

Last year, in a stab at public relations glory, investment bank Macquarie got a team of its human analysts, plus an artificial intelligence it had assembled, “PunterGPT”, to predict the winner of the Melbourne Cup.

Both were wrong.

The Melbourne Cup 2024 was won by King’s Choice in what pundits described as a “huge upset” and a “massive boilover”.

PunterGPT had picked Vauban, who placed 11th.

Macquarie’s human analysts did even worse. They picked Sea King, who finished 14th.

For the 2025 Melbourne Cup this afternoon, Macquarie’s humans have picked Half Yours, the bookies’ favourite.

PunterGPT – which Macquarie says is powered by OpenAI’s ChatGPT, Anthropic’s Claude, Google’s Gemini and Elon Musk’s Grok – has also backed Half Yours to win.

The heavily-backed Half Yours won the Caulfield Cup last month and could become only the 13th horse to win a Melbourne Cup double.

Meanwhile, the Department of Internal Affairs is reminding Kiwis of the rules for running an office sweepstake.

They include:

• Prizemoney can’t exceed $500 unless you are a society.
• All money raised must be returned as prizes.
• Firearms, alcohol, vouchers for sexual services and tobacco are examples of prohibited prizes.
• The organiser can’t pocket a fee or profit in any way from running a sweepstake.

Not following the rules can result in a fine of up to $20,000.

Chris Keall is an Auckland-based member of the Herald’s business team. He joined the Herald in 2018 and is the technology editor and a senior business writer.