Controversial taxi hire app Uber is on the verge of raising $1 billion (£633 million) in a move that could see the firm valued at up to $40 billion (£25 billion).
The company, which has disrupted London's black cab industry, has attracted US investors T.Rowe Price Group and Fidelity Investments, according to Bloomberg.
Uber was valued at $17 billion (£10.8 billion) in June after it raised $1.2 billion (£750 million) from seven investors.
The latest valuation dwarves those os Twitter, Airbnb and Snapchat, which have market caps of $25.1 billion (£15.9 billion), $13 billion (£8.2 billion) and $12 billion (£7.6 billion) respectively.
Uber has proved controversial in many of the cities it operates in, with licensed taxi drivers claiming the firm is breaking the law because its cabs don't have a regulated meter. The app has also received temporary bans in Germany.
Last week Uber confirmed it was going to investigate one of its New York executives for allegedly tracking a journalist's movements without her knowing.
In a separate incident last week, another Uber executive said the company should create an army of private investigators to track the private lives of journalists who reported on the company.
This story, "Uber to Overtake Twitter in Market Cap Stakes as It Looks to Raise $1B" was originally published by Techworld.com.