The boots are typically made of twin-faced sheepskin with fleece on the inside, a tanned outer surface and a synthetic sole.
In Australia, they are worn predominantly as slippers and often associated with daggy fashion sense and bogan culture.
[3][4][5][6] Outside Australia and New Zealand, UGG is a brand manufactured by the California-based Deckers Outdoor Corporation, with most of its manufacturing based in China and with registered trademarks in over 130 countries worldwide including the US, UK, Canada, all European Union members, and China.
"[21][22][17] Some accounts have suggested that the term grew out of earlier variations, such as the "fug boots" worn by Royal Air Force pilots during World War I.
[29] Seeing the popularity of the boots among American surfers, Australian surfer Brian Smith, then living in Santa Monica, California, and colleague Doug Jensen bought boots from Country Leather but were unhappy with the brand and decided to register UGG as their own trademark.
[32] Australian manufacturers also saw an increase in exports of sheepskin boots to the United States, although Ugg Holdings retained an estimated 80% market share.
By the end of the year, Country Leather had opened its own shop in Redondo Beach to promote an expansion of the brand from its established surf market into mainstream footwear sales and Ugg Holdings began sourcing UGG boots directly from Jackson's Tannery, which had changed its name to EMU Australia.
[2][37][38][39] According to Australian fashion stylist Justin Craig: "The only people who get away with wearing them are models, who give out the message: 'I'm so beautiful, I can look good in any crap.
[11][40] Deckers solicited endorsements from celebrities such as Kate Hudson, Sarah Jessica Parker,[30][41] Cameron Diaz, Leonardo DiCaprio and Jennifer Lopez,[42] and product placements in television series such as Sex and the City, and films such as Raising Helen.
Some ugg boots have a synthetic sole, commonly made from Ethylene-vinyl acetate (EVA).
[48] Produced by a number of manufacturers, they come in a variety of colours, including black, pink, blue, chestnut, and fuchsia.
Although derided as "fake" by some in the industry, their lower price made them appealing to large retail chains such as Myer.
[52] Animal rights groups call for the boycott of sheepskin boots and their replacement with synthetic alternatives.
[53] In 2007, Pamela Anderson, realizing that the boots were made of skin, called for a boycott on her website.
[4] Outside Australia and New Zealand, UGG (written in capital letters) is a registered trademark of Deckers Outdoor Corporation.
[5][36] In 1999, Deckers began asserting its new trademark and sent out cease and desist letters to Australian manufacturers that were selling sheepskin boots outside of Australia via the internet.
Deckers' law firm Middletons of Melbourne began a serious effort to halt the Australian companies' sales[4] by sending cease and desist letters to a number of Australian and U.S.-based manufacturers, preventing them from selling sheepskin boots using the UGG trademark on eBay or from using the word in their registered business names or domain names.
[4] The officer who heard the case stated that the "evidence overwhelmingly supports the proposition that the terms (ugg, ugh and ug boots) are interchangeably used to describe a specific style of sheepskin boot and are the first and most natural way in which to describe these goods."
[4][5] This 2006 ruling applies only in Australia and Deckers still owns the trademarks in other jurisdictions such as the US, China, Japan and the European Union.