Fidelity's bets on unicorn companies put a dent in the stellar performance of some of the company's most popular mutual funds during the first half of 2017. The Boston company has stepped up disclosure of how pre-IPO companies affect mutual fund performance. This week, for example, Boston-based Fidelity Investments showed how content-sharing company Pinterest Inc. had an outsize impact on the portfolio performance of its most popular stock fund. Read the original story from Reuters.