Nubank has submitted confidential paperwork for its U.S. IPO.

Sao Paulo-based Nubank, a fintech and challenger bank backed by Warren Buffett’s Berkshire Hathaway (NYSE: BRK.A), is hoping to raise $3 billion at a valuation of $50 billion in its upcoming U.S. IPO. (Reuters)

Nubank is looking to sell 289 million shares in its IPO in the price band of $10 – $11 per share, according to a Monday filing.

At a valuation of $50 billion in the IPO, Nubank would substantially improve on the $30 billion tag it achieved in June when it raised $750 million in a funding round that included an investment of $500 million by Warren Buffett’s Berkshire Hathaway.

Nubank’s IPO would be among the biggest U.S. IPOs this year, including from e-commerce firm Coupang (NYSE: CPNG), Chinese ride hailing company Didi Global (NYSE: DIDI) and chipmaker GlobalFoundries (NASDAQ: GFS).

It would also place Nubank in the ranks of Latin America’s largest listed companies, and give it a market capitalization higher than that of Itaú Unibanco, a legacy bank in Brazil. The traditional banking industry in the country has long been criticised for high-priced charges for poor services.

Filing documents showed Nubank’s revenues had nearly doubled to $1.06 billion in the nine months to September 30, though losses surged from $64.4 million to $99.1 million.

The shares will trade on the NYSE under the ticker symbol NU.

Post-IPO, co-founders Velez, Cristina Helena Zingaretti Junqueira and Adam Edward Wible will hold a 25% stake in the company but will control 87% of the voting power.

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