Domain Holdings Australia (ASX:DHG) said CoStar raised its offer to AU$4.43 cash per share from AU$4.20, according to a Thursday filing with the Australian bourse.
The revised offer represents a 5.5% premium to the original offer.
The offer is final and subject to Domain's board's recommendation and an exclusivity agreement, the filing said.
Domain may also pay a pre-completion dividend with franking credits worth up to AU$0.04 per share, the company said.
Following discussions with its largest shareholder, Nine Entertainment Co. Holdings (ASX:NEC), the company determined to grant due diligence access to Costar.
In a separate filing, Nine said it supports the company's decision to grant due diligence access to Costar, adding that it would earn cash proceeds of about AU$1.4 billion, net of capital gains tax, on completion of the deal at the revised price.
Domain's shares fell 4% in recent Thursday trade, while Nine Entertainment's shares lost nearly 1%.
Price (AUD): $4.28, Change: $-0.19, Percent Change: -4.25%