Retail investors may not be the only ones profiting from the epic short squeeze on shares of GameStop (GME 7.58%) that has captivated market audiences everywhere.

The world's largest asset management company, BlackRock (BLK -0.50%), held a roughly 13% stake, or 9.2 million shares, in the video game retailer at the end of 2020, according to a Securities and Exchange Commission filing.

Since then, retail investors fueled by the subreddit WallStreetBets, who noticed the amount of short interest on GameStop, have banded together to drive the stock higher by pledging not to sell shares.

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Image source: Getty Images.

The surge in GameStop shares forced short-sellers to repurchase the shares they borrowed at a higher price, only adding fuel to the stock's upward momentum. At one point earlier today, GameStop briefly touched $500 per share, plummeting all the way to $135 in the late morning.

There has been no filing yet to suggest that BlackRock has sold its position, although it certainly could have.

But assuming it didn't, shares of GameStop traded for less than $19 per share on the last day of 2020, when BlackRock last reported its position, which would have given BlackRock a nearly $175 million stake in the company.

Now, that stake could be worth anywhere from $2.8 billion, when GameStop traded at $300, to $4.6 billion (when it briefly touched $500).

Another asset management company that looks like it benefited from the squeeze on GameStop is MUST Asset Management, based in South Korea. The company revealed a 5% stake, or 3.3 million shares, back in March of 2020.

GameStop's stock closed at $4.19 on March 19, 2020, valuing MUST's position at roughly $13.8 million. On Jan. 27, a new regulatory filing showed that MUST no longer owned any shares of GameStop.

At GameStop's closing price of $347.51 on Wednesday, Jan. 27, that would value MUST's stake at about $1.1 billion.