The $52 million partial takeover offer for Wakefield Health will give the Christchurch-based Stewart family a new stake in the private healthcare industry, through its investment vehicle Masthead Holdings.
Austron, which is a joint venture entity owned by Royston Hospital Trust Board and Masthead Holdings subsidiary Medusa, is offering $6 a share for just over 50% of Wakefield.
Royston and Medusa have just under 20% each in Wakefield and Austron says it has also secured about 5% of AMP Capital Investors' 16% stake and can take more if need be, to ensure its bid is successful.
Craigs Investment Partners head of investment management James Beale says Austron's intentions are not clear but the majority stake will give it some options.
He says the business has a strategic position in the New Zealand private hospital market so is an attractive proposition for acquisition.
However, there are already questions about whether the offer could be stymied by takeover rules.
All investors who want to sell will have just over 50% of their shares accepted, and James Beale says that unusual structure raises a technical issue.
"It's only a partial offer at this stage but if other investors do accept, given that they've got AMP over the line already, there will be scaling which would leave a residual shareholding directly for Medusa and Royston, which really takes their effective control beyond 50%", he says.
Shareholders will be sent the offer on August 9.