Allbirds, the eco-chic footwear brand co-founded by former All White Tim Brown, has agreed to sell its 'intellectual property and certain other assets' to American Exchange Group.

The brand will be sold for an estimated value of $68 million NZD - a fraction of the company's original net worth.

NZ Herald senior business writer Chris Keall says the company's been in decline for years - with too many key factors going wrong. 

"The overarching thing is that it's never been able to make a profit, but it's making sustainable shoes from New Zealand merino wool and recycled materials - but not at a sustainable price."

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