Berkshire Hathaway (NYSE:BRK.A)(NYSE:BRK.B) has had a difficult time finding places to put its money to work in recent years, and this has led to the company branching out into more tech-focused investments.

One area that is a natural fit for Buffett and his team is financial technology, or fintech. Banking has long been a favorite industry of Buffett's, and that's obvious in the company's massive stock portfolio -- in fact, Bank of America (NYSE:BAC) is Berkshire's second-largest investment.

So, when looking to branch out into newer technologies, the financial sector certainly makes sense. We've already seen fintech investments from Berkshire such as Brazilian payment processor StoneCo (NASDAQ:STNE) and India-based mobile payments company Paytm, and we just learned that another has been added.

Two young women paying for purchases with credit card.

Image source: Getty Images.

Berkshire's latest fintech investment

It was reported on Tuesday that Berkshire has invested $500 million in another Brazilian fintech start-up called Nubank, which is best known for issuing credit cards. Nubank, which is private, raised a total of $750 million in new funding (including Berkshire's) at a valuation of $30 billion. 

Nubank currently has 40 million customers and plans to expand its operations into Mexico and Columbia, and there have previously been rumors that the company is eyeing a U.S. IPO in the not-too-distant future.

StoneCo has been a highly successful investment for Berkshire, up by about 160% from the $24 share price Berkshire paid at the time of the fintech's late-2018 IPO, and Berkshire is clearly hoping for a repeat of its initial success in the Brazilian fintech market.

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