SoftBank is also investing $1.25 billion in new capital in Uber at its most recent $70 billion valuation.
Uber will use the SoftBank funding to invest in its technology, fund its growth and revamp its corporate governance, an Uber spokesman said in a statement. On Thursday it said that existing investors had agreed to sell enough shares for SoftBank to go through with the transaction.
The investor group is also buying about $1.25bn worth of new shares at a price that values the firm at nearly $70bn, a significantly higher price that is similar to what Uber shares fetched in its last fundraising round.
"We look forward to working with the purchasers to close the overall transaction", the Uber spokesperson said.
Rajeev Misra, the chief executive of SoftBank's Vision Fund, a $98bn tech investment vehicle, will join the Uber board, along with a second representative from SoftBank.More news: Daughter of police victim declared brain dead
Lucky for Uber, the company will still retain its title of "most valuable startup", as second place goes to WeWork, which is now valued at $31 billion.
Some initial investors in the consortium, including General Atlantic, dropped out over disagreement about the price offered to shareholders, Reuters previously reported.
When the deal is completed, the company will make governance changes, including expanding its board from 11 to 17 members including four independent directors, limiting some early shareholders' voting power and cutting the control wielded by former chief executive Travis Kalanick.
SoftBank has previously pumped billions into several ride-hailing companies overseas, including Didi in China, Grab in Southeast Asia and 99 in Brazil.
Uber said the investment would fuel its expansion and technology investments.