Chairman Rod McGeoch said in a statement, "The company continues to caution shareholders that there is no assurance that any of the approaches received will result in any specific transaction."
Shares in Sky City, which has a virtual monopoly on casinos in New Zealand and also operates Australia, last traded up four cents or 0.8 percent at NZ$5.37, having gained 9.8 percent so far this year, compared to a 6.4 percent rise for the benchmark top 50 index.
Private equity or global gambling operators have been touted as the most likely source of bids. Analysts say a private equity bidder could offer up to NZ$5.75, while a trade bidder may go as high as NZ$6.40, which would value the company at NZ$2.9 billion (US$2.2 billion).
The first approach from an unknown company, tipped by local media as likely to be private equity firm TPG, was in late September, with the company expressing an interest in acquiring Sky City in an all-cash offer at a significant premium to the then market price.
Australian competitors of Sky include Tabcorp Holdings, Tattersall's and Publishing and Broadcasting. Both Tabcorp and Tattersall's have said they are not interested.
Sky City has a current enterprise value-to-earnings before interest, tax, depreciation and amortization (EV/EBITDA) of 11.7, compared to a ratio of 10 for Tabcorp, and 13.7 for Tattersall's.
Citigroup has said in a report that recent Australasian casino deals had an average EV/EBITDA ratio of around 10 times.
In May, Sky City unveiled a program of cost cutting and possible asset sales after posting disappointing results, which led to the chief executive quitting in June.
Toime candidly admitted that the company had not performed well. "Our last financial year was pretty disappointing. The main reason is that we've undertake a very significant refurbishment NZ$40 million program, running almost 18 months. That has been very disruptive for our customers and that's slowed things down altogether," Toime said.
But Toime added that, "We think when we come out of that next year, we will have a very spectacular venue and that will reawaken interest."