"I never wanted to be a businessman," he explained. "I started as a craftsman, making climbing gear for my friends and myself, then got into apparel."
He added: "As we began to witness the extent of global warming and ecological destruction, and our own contribution to it, Patagonia committed to using our company to change the way business was done."
Founded almost 50 years ago, Patagonia quickly became committed to conserving nature, by carefully choosing its raw materials and donating one percent of its sales each year to environmental NGOs.
But Chouinard has decided this is no longer enough.
One option was to sell Patagonia and donate the money. "But we couldn't be sure a new owner would maintain our values or keep our team of people around the world employed," he said in the letter.
Taking the company public would have been a "disaster," he said: "Even public companies with good intentions are under too much pressure to create short-term gain at the expense of long-term vitality and responsibility."
Patagonia will remain a company, which cares about its financial health and will operate with a board of directors and CEO.
The Chouinard family will no longer get any money from the company but will stay on the board, as well as oversee the trust and guide the nonprofit's philanthropic work.
