
In today’s briefing:
- MAC Copper (MAC AU/MTAL US): 29th August Vote On Harmony’s Offer
- Rio Tinto (RIO AU): Post-Earnings Drop Exceeds Expectations

MAC Copper (MAC AU/MTAL US): 29th August Vote On Harmony’s Offer
- Back on the 27th May 2025, dual-listed MAC Copper (MAC AU/MTAL US), a NSW copper miner, entered into a Scheme Implementation Deed with Harmony Gold Mining (HAR SJ).
- Harmony offered US$12.25 for each MAC Share, a 20.7% premium to last close. The A$ consideration for MAC CDIs pivots off the USD/AUD exchange rate around the Record Date.
- A copy of the Circular is now available, with a shareholder vote on the 29th August. Barrenjoey, the FA, says fair & reasonable. 22.54% of shares out are supportive.
Rio Tinto (RIO AU): Post-Earnings Drop Exceeds Expectations
- Context:Rio Tinto Ltd (RIO AU) reported 1H25 results on 30 July, cutting its interim dividend by 16%.
- Rio Tinto’s share price fell more than expected after earnings, exceeding both historical and implied moves. A surprise US copper tariff announcement further amplified the decline.
- This Insight breaks down drivers of the post-earnings move and evaluates the potential outcome of a short-vol strategy — offering a practical case study for refining similar trades.