The optimal portfolio of start-up firms in venture capital finance

Venture capitalists (VCs) not only finance but also add value to start-up companies. Advising firms is time consuming and creates a trade-off between intensity of advice and portfolio size. We jointly determine the optimal number of portfolio companies and the intensity of managerial advice. Diminishing returns to advice per firm call for a larger portfolio. With progressively increasing managerial effort cost, however, a larger number crowds out advice to each individual firm. As they receive less support, entrepreneurs request a larger profit share, making further portfolio expansion eventually unprofitable. Comparative static analysis shows how optimal portfolio size responds to venture returns and other parameters.