Fidelity Investments has become one of the most active investors in privately-held startups, buying into popular companies and then divvying up the shares among its various mutual funds. Now, however, it looks like the investment giant is beginning to reconsider the prices it paid just earlier this year.

Yesterday came reports that Fidelity had marked down the value of its investment in Snapchat by around 25% between the end of July and the end of September, based on an investment it had made just this past spring. Most of that stock is held by Fidelity in its Blue Chip Growth Fund, a $69.5 billion mutual fund that primary invests in S&P 500 or Dow Jones Industrial Average companies, but which also has plugged around $300 million into privately-held growth companies like Snapchat.

Fortune has reviewed these holdings, and learned that Snapchat is hardly the only one to receive a serious markdown over the past few months. In fact, others have fared far worse.

Take Blue Bottle Coffee Co., for example. Fidelity led a $70 million investment for the trendy coffee chain this past May, investing just over $21 million. It held that investment at cost through the end of July but, as of Sept. 30, it was marked down a whopping 43.3% — perhaps due to Blue Bottle’s decision to kill off its wholesale business, although that announcement came in June. Or what about Zenefits, officially known as YourPeople, the popular HR automation platform in which Fidelity first invested back in May? The mutual fund slashed the value of those shares by 48%. Or Dataminr, a big data startup that analyzes social media, which has been marked down by 35%.

And then there ins NJoy, the electronic cigarette maker that has raised over $160 million. Fidelity owns three different types of NJoy securities, but has all but written them off entirely. Its $4.91 million investment from June 2013 is now valued at just $300,000. Its $2.5 million investment from February 2014 is now valued at just $70,000. And, even worse, what appears to be a $9.52 million common stock investment from Sept. 2013 has been written down to just $12.

Overall, the Blue Chip Growth Fund is carrying its privately-held companies above cost — thanks in large part to appreciation in shares of Uber and The Honest Company (both of which were static between July and September). But of the 23 companies we examined , more than one-third were marked down between July and September (not including five portfolio additions during the period). Only a small handful were marked up, while the rest remained static.

It is worth noting, of course, that marking values of private companies is more art than science, which is why most traditional venture capital firms only change their valuations when there is a subsequent financing event. But Fidelity clearly is feeling some frost.

Below is a list of private holdings in Fidelity Blue Chip Growth Fund:

UPDATE: We’ve posted a follow-up story, with valuations from a different Fidelity mutual fund and more info on how the firm determines these marks. Read it here.