If you live in Europe and you use a neobank, you’ve likely been interacting with Upvest’s investment products without even knowing it. The Berlin-based startup runs a stock-trading API that integrates into some of the biggest fintechs in Europe — Revolut, N26, Bunq, Plum, Raisin, Shares and Vivid. Through these banks, some 50 million users have access use the company’s investment products, it said.