Thousands of Aussie taxi and car-hire drivers are suing the ride-hailing giant Uber, just days ahead of the company billion-dollar initial public offering (IPO) of its stock.

"It is shaping (up) as one of the largest class actions in Australian history," said Andrew Watson, head of class actions with the lawfirm Maurice Blackburn.  "Make no mistake, this will be a landmark case regarding the alleged illegal operations of Uber in Australia."

The plaintiffs and more than 6,000 strong.  They accuse Uber of taking unfair advantage over taxi and hire-car industry participants who were complying with the law, destroying their livelihoods.  The suit alleges Uber entities knew their operations in Australia were illegal for a number of reasons, including that the company "adopted a policy to operate in any market where the regulator had tacitly approved doing so by failing to take direct enforcement action".

This comes as Uber is preparing to sell 207 million shares in its US IPO, which is expected to raise up to US$10 Billion.  But while the investment world is salivating over the opportunity, the folks closer to the real streets are less than impressed.

"It is a dud investment dressed up as something innovative," said Tony Sheldon of the Transport Workers' Union to the ABC.  "Its business model is based on exploitation, lies and illegal activity," he added.

Uber denies the pariah status the lawsuits seeks to assign, says that it is the "reliable choice" used by millions of Australian consumers, and added that as of earlier today it had not been informed of the class action lawsuit.