Genesis Minerals Ltd's stock fell 5.72% during intraday trading on Monday, as investors reacted to the company's announcement of a rival takeover bid for fellow Australian gold miner Vault Minerals Ltd.

The company has made an unsolicited binding proposal to acquire Vault Minerals at a valuation of approximately A$5.6 billion (US$3.9 billion), which represents a 15.7% premium to Vault's last closing price and is nearly 6% above a previous all-scrip offer from Regis Resources. Under the terms, Vault shareholders would receive 0.7629 new Genesis shares plus A$0.475 in cash for each Vault share held.

Vault Minerals has declared the Genesis proposal a "superior proposal" compared to the Regis deal and has notified Regis of a five-business-day matching right period. If completed, Genesis shareholders would own approximately 60% of the enlarged company, raising concerns among investors about potential share dilution and the costs associated with the large acquisition in the competitive gold mining sector.