Investors in traditional equity funds may be exposed to crypto without even knowing it. New research from analytics firm Markov Processes International suggests that several ETFs and mutual funds that aren’t labeled as cryptocurrency vehicles show signs of at least indirect exposure to bitcoin.

MPI used returns-based style analysis to evaluate the daily returns of over 1,500 U.S. equity funds to estimate their bitcoin exposure. s. Using Invesco’s QQQ as a baseline (since it has some indirect bitcoin exposure through its holdings), MPI identified “an almost linear relationship” between funds with higher estimated exposure and higher volatility than the broad equity ETF.

VanEck’s BUZZ ETF, for example, showed substantially higher indirect exposure, estimated at roughly 18.5 percent, leading to annualized volatility of around 36 percent — roughly 50 percent greater than QQQ. By comparison, Cathie Wood’s highly volatile ARKW ETF has much more direct bitcoin exposure than QQQ or even BUZZ — roughly 25 percent, the highest in MPI’s sample — from allocating to a bitcoin ETF and holding crypto-linked stocks like Coinbase and Tesla. ARKW’s share price has fluctuated more than 130 percent between its 52-week low of $78.62 and high of $183.00 as of December 16.

MPI estimates that there are dozens of funds that have anywhere from twice to five times more bitcoin exposure than QQQ “without any obvious ‘digital assets’ branding or headline holdings.” According to the research, “this kind of hidden exposure inevitably leads to a roller-coaster ride whenever BTC takes a dive or launches into another vertical rally.”

“If you’re a long-time crypto investor, you already know this is part of the game,” the report states. “But what if you don’t own BTC directly and instead hold mutual funds and ETFs? How do you know what kind of ride you’re really signed up for … when Bitcoin moves 20 to 30 percent in a day??”

That hidden crypto exposure poses serious challenges for equity investors who never signed up for this level of risk. While cryptocurrency volatility is down from the nearly 100 percent annual price fluctuations it experienced in its early days, it’s still “now moderating at more like 50 percent volatility,” Donald Putnam, managing partner at the San Francisco-based investment bank Grail Partners, recently told Institutional Investor.

He added that what began as an uncorrelated asset now shows “significantly more correlation, both with equity markets and with interest rates.”

Bitcoin’s price dropped to around $85,000 on Nov. 21, down 31 percent from its peak of more than $126,000 in early October. Its price was hovering around $87,000 in mid-December.