Australia’s largest gold miner, Northern Star Resources, has unanimously rejected an unsolicited A$38.7-billion (US$27.1-billion) takeover proposal from South Africa’s Gold Fields, saying the offer materially undervalued the company and was made at a “highly opportunistic” time.

The proposal, received on September 14, 2026, sought to acquire 100% of Northern Star’s shares through a scheme of arrangement. Under its terms, shareholders would have received 0.3125 new Gold Fields shares and A$7.25 in cash for each Northern Star share.

Based on Gold Fields’ closing share price on September 11 — the last trading day before the approach — the offer implied A$27.00 per Northern Star share, a 22% premium to its closing price at the time.

However, a subsequent decline in Gold Fields’ share price reduced the implied value to A$25.19 per share as of September 25, lowering the implied equity valuation to approximately A$36.1 billion.

Northern Star Chairman, Michael Chaney said the board concluded the proposal “materially undervalues” the company and exposed shareholders to additional risks.

“Gold Fields has sought to acquire one of the world’s premier gold portfolios at a price that falls well short of what the Board considers to be its fundamental value and at a highly opportunistic time,” Chaney said.

The board raised specific concerns about the structure of the offer. Approximately 73% of the proposed consideration consisted of Gold Fields shares, which Northern Star said would expose its shareholders to “operational and jurisdictional risks associated with Gold Fields that they do not currently face”. Had the transaction proceeded, Northern Star shareholders would have owned about one-third of the combined company.

Directors also said the approach arrived ahead of key value-creating milestones, including the commissioning and ramp-up of the Fimiston Mill and the arrival of incoming Managing Director and CEO Suresh Vadnagra.

The offer was subject to several conditions, including due diligence, regulatory approvals, Gold Fields shareholder approval and a requested period of “hard” exclusivity without a fiduciary-out provision — requirements Northern Star said would create prolonged uncertainty and material completion risk.

The company informed Gold Fields on September 25 that it did not consider further engagement appropriate.

Northern Star shares rose as much as 10.6% to A$24.46 in early trading on Monday, the highest level since August 28, before trading around 8.3% higher at A$23.95. The shares remained below the implied offer price, reflecting market scepticism about the likelihood of a revised bid at the original terms

The approach comes amid sustained pressure on Northern Star from activist investor Elliott Investment Management, which holds approximately 6.24% of the company following a series of operational setbacks and guidance downgrades.

In June, Elliott urged Northern Star to conduct a strategic review that it said could result in a sale to a rival such as Gold Fields.

Elliott Partner John Pike said on Monday that the investor believed there was “immense potential for value creation” at Northern Star that any transaction would need to reflect. “But others clearly see the value here too, and we think the Board has an obligation to engage with any serious buyer and fully evaluate the best path to deliver on that potential,” Pike said.

For Gold Fields, a successful deal would significantly deepen its exposure to Australia, which already accounts for more than 40% of its production. The company expanded its Australian footprint in 2025 with the A$3.7-billion acquisition of Gold Road Resources, securing full ownership of the Gruyere gold mine in Western Australia.

Gold Fields estimates potential synergies of between US$4 billion and US$5 billion from the close proximity of the two companies’ assets.

Both miners operate in Western Australia’s Goldfields region. Northern Star runs the Kalgoorlie Consolidated Gold Mines — known as the Super Pit — Australia’s largest gold mine.

The bid is the latest sign of consolidation pressure in the global gold sector. A successful takeover of Northern Star would rank among the largest-ever acquisitions of an Australian company. Gold Fields did not immediately comment on Northern Star’s rejection.

The company has previously signalled it would consider its next steps, and analysts expect it may take its case directly to Northern Star shareholders.

Northern Star’s portfolio includes long-life, tier-one assets in low-risk jurisdictions, with group mineral resources of 88.9 million ounces and ore reserves of 28.4 million ounces as of March 31, 2026. The board’s rejection signals it intends to pursue that growth trajectory independently, at least for now.