Graeme Hart is exploring a sale of drinks and food packaging maker Sig Combibloc that could value the business at around US$5 billion.
Citing unnamed sources, Reuters reported that Hart's packaging conglomerate, Reynolds Group Holdings, has hired Goldman Sachs to "explore alternatives" for Switzerland-based Sig including a potential sale.
Hart, New Zealand's richest man, acquired Sig for US$2.3 billion in 2007.
Reuters reported that the company had earnings before interest, tax, depreciation and amortisation (ebitda) of around US$500 million and the sale was expected to attract interest mostly from private equity firms.
Sig posted total revenue of 1.7 billion euros last year, according to its website.
The company manufactures aseptic carton packaging that allows food to be stored for a long period of time without refrigeration.
A successful sale of Sig would help Hart reduce a US$18 billion debt pile accumulated through a number of leveraged buy-outs, Reuters reported.
They included a US$6 billion buy-out of Pactiv Corp, whose brands include Hefty rubbish bags, in 2010 and a US4.5 billion acquisition of Graham Packaging Co the following year.
In April Hart's Rank Group revealed it had sold Carter Holt's pulp, paper and packaging businesses for $1.037 billion to Japan's Oji Holdings and Innovation Network.
Hart's wealth was estimated at NZ$6.4 billion in last year's NBR Rich List.