Walk around the boutique-like showrooms in Li & Fung’s Hong Kong headquarters and you could be in any western shopping mall, albeit with a nagging feeling that you can’t quite place the store you are in. Then it becomes clear – Li & Fung supplies them all.

If you’ve bought shoes from Calvin Klein or Coach, DKNY jeans, clothes from American Eagle or Aéropostale, or anything from Tommy Hilfiger, Helly Hansen, Juicy Couture or Kate Spade then you own products sourced and supplied by Li & Fung, the invisible support to many of the world’s most recognisable brands and stores, from Walgreens and Walmart to Marks and Spencer and J Sainsbury. Ever wondered who found the materials to produce the eye-catching flower-shaped stoppers on Marc Jacobs’ perfumes or the metal band surrounding Chanel Chance bottles? From heated eyelash curlers for Dior to Hello Kitty products priced for US dollar stores, Li & Fung is probably the only source of consumer goods producing $20bn a year in revenues that shoppers have never heard of – even as it became a market darling and a feted business school case study for its application of strategic thinking to the Asian supply chain.

But investor adoration is turning to doubt. The company is the biggest loser in Hong Kong’s Hang Seng index over the past year – off 30 per cent. This month it warned of a two-fifths drop in operating profits. Its stock is hovering near three-year lows. Was the profit warning, as Li & Fung said, because of a costly restructuring that will leave it better placed to serve its mostly western customers? Or is something far more serious going on?