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It might be easier to delete Facebook from your phone than your 401(k) plan. The social media company tumbled more than 20 percent this week, erasing more than $120 billion of its market value. Users have been fleeing the company amid scandals over its data use and collection, and it recently admitted it needs to revise its business practices. In the meantime, because of the company's profound size and scope, its losses are likely to impact investors of all stripes. "You should just assume you own Facebook," said Jamie Cox of Harris Financial Group, which manages $500 million for about 800 middle-class families. "It would be hard not to if you have any growth funds in your portfolio."

Are you invested?

Of course, a big question for many investors is "do you know if you actually have Facebook in your portfolio?" "The sad part of this is that the majority of people can't name one mutual fund in their 401(k)," said Ted Jenkin, CEO and founder of oXYGen Financial in Atlanta. Many mutual funds, exchange traded funds, 529 plans, 401(k) plans and individual retirement accounts hold Facebook. "Plenty of the larger mutual funds have Facebook as one of the top five holdings," Cox said. Investors should go online and look at their annual report to see if they're invested in tech funds, Jenkin said. If they are, they'll want to check the top 10 holdings of the portfolio to see how much of it might be held in the company. But don't hyper-focus on the stock, many experts say. Instead, look at how the entire fund or index is performing.

There might not be much you can do