Nu Holdings is a high-quality business backed by billionaire investors with a long-term commitment. The stock price of Nu Holdings (NU -2.06%), a fintech company based in Latin America, has had a strange journey. In 2022, its shares lost more than 50% of their value. Then in 2023 the stock more than doubled in value. This is a volatile holding, but underneath is one of the highest-quality businesses on the market today. And the company happens to be backed by several billionaire investors, including an inve ...