'Shark Tank' star Kevin O'Leary says he's buying the dip in Facebook parent Meta after the stock's record one-day crash

• Kevin O'Leary told CNBC he's going to buy Facebook parent Meta as institutions adjust their holdings
• The "Shark Tank" star noted Facebook is still one of the biggest ad platforms in the world.

Billionaire investor Kevin O'Leary says he's going to buy the dip in Facebook parent Meta's shares, which suffered their biggest one-day drop ever Thursday.

Meta's stock dropped 26%, wiping $200 billion off its market capitalization, after a disappointing fourth-quarter earnings report that showed Facebook shed daily users for the first time ever.

But Meta is mainly owned by institutional investors that will adjust their holdings lower, rather than sell the entire position, O'Leary told CNBC's Fast Money on Thursday.

Once that happens, possibly in the next few days, there will be an opportunity to buy the dip — something that the "Shark Tank" star plans to do.

"You've got to wait until they flush down their positions to that 3.5%, 3%, 2% position. The majority of them are not going to zero, they're going to reposition it with the risk inherent," he said.

"And for those that were at 2 % or 3% — they're going to buy into the flushing, and that's what I'm doing."

"I"m going to bring my weighting back up to a max weighting, take advantage of a 24-25-26 discount. But you don't have to do it all today — there's a lot of toilet flushing left on Facebook."

Investors ditched Meta in droves after the social media giant's worse-than-expected quarterly earnings, where it said rivals like TikTok had hit its revenues. The company said its ad business stands to lose $10 billion this year, after Apple made an iPhone privacy change affecting user tracking.

Even so, Facebook remains one of the biggest ad platforms in the world, with billions of users, O'Leary noted — and that's why not every institution is going to sell it down to zero.

Meta was trading at $232.58 on early Friday, down just over 2%, after starting the week at $301.71.

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