Business development companies, aka BDCs, are the stock market’s answer to venture capitalism for individual investors. By buying shares of BDCs, shareholders indirectly invest in start-ups, which are typically only accessible to accredited, very high-net-worth investors through venture capital and private equity firms. BDCs finance and invest in private, small- to mid-sized firms, with annual sales of $10 million to $300 million, in an array of industries.