The company that owns the Bluebridge ferry has been put on the sales block, according to Australian media reports.
The Australian Financial Review (AFR) is reporting that StraitNZ's owner, Sydney-based CPE Capital, had taken steps to find a new buyer for the company.
StraitNZ was started 29 years ago and includes the passenger ferry service and a freight forwarding business.
CPE Capital bought the company four years ago and had been preparing the firm for sale to take away market share from the state-owned IntersIslander service, the AFR reported.
StraitNZ's website said it owns two ferries and 150 vehicles, and operated a nationwide network of depots which employed more than 500 staff.
The AFR reported the company generated about $175 million in revenue each year, which flowed through to earnings of $45m.
StraitNZ has been approached for comment.