Synlait Milk founder and chief executive John Penno is to step down after 12 years leading the Dunsandel-based milk processor, whose shares have almost tripled since listing in July 2013.
Penno will step down in the next 12 months in what the company said would be an orderly transition. He will stay on during an international search for his successor.
Penno, who has spent a total of 17 years with the company, said he was "looking forward to getting back to my entrepreneurial roots and will be looking for opportunities to get involved with start-ups and young companies, which is where my wife, Maury, and I want to continue to make a contribution."
Synlait has grown from a start-up in the early 2000s to a company with a market value of $1.4 billion today and customers including high-flying milk marketer A2 Milk.
It was initially rebuffed in its attempts to go public by local investors and instead turned to China's Bright Dairy for equity capital to fund its growth. Bright Dairy now owns 39 per cent of the company.