Uber's bumpy ride over the years

CONTENTIOUS MOMENTS IN THE LIFE OF UBER:

* In July, chief executive Travis Kalanick, who helped found the company in 2009, resigned following scandals and criticism of his management style.

* A month earlier, the company sacked 20 people including some managers after a law firm investigated complaints made to the company about sexual harassment, bullying and retaliation for reporting problems.

* In May, hundreds of taxi drivers in Poland's four largest cities drove at a crawl during rush hour in protest against the rise of services such as Uber.

* In February, thousands of Italian taxi drivers clashed with riot police during a week-long strike against Uber that crippled transportation in Rome, Milan and Turin.

* Uber ended in Denmark this year following the introduction of new, tougher taxi laws.

* At the start of 2017, the firm paid $US3 million ($A3.8 million) in the US to settle allegations it gave false promises to drivers over how much they would earn.

* In October 2016, Uber lost a landmark employment tribunal ruling its drivers should be classed as workers rather than being self-employed. It had claimed its employment arrangements allowed its drivers across England and Wales to be their own boss and work flexibly but the panel gave a scathing dismissal of Uber's arguments.

* A few months later, Uber announced it would offer English courses, financial advice and introduce an appeals panel for its UK workers after facing criticism over lack of support and rights for its drivers.

* In 2015, the New Delhi government banned app-based taxi companies after an Uber driver raped a passenger in his vehicle. Uber lost its licence in the Indian capital for a time, having failed to carry out proper background checks on drivers.

* Uber stopped operating in Austin, Texas, when it was told drivers would have to have fingerprint background checks but it reinstated its services after the requirement was ended.