Activist investor Ryan Cohen has scored a 25x gain on his GameStop bet - and now commands a $1.9 billion stake

• Ryan Cohen has scored a 25-fold gain on his GameStop bet in eight months.
• The Chewy cofounder spent $76 million for a stake worth $1.9 billion today.
• Cohen is a key reason why GameStop shares have soared more than 1,000% this year.

Ryan Cohen has scored a roughly 2,400% gain on his GameStop investment in eight months, valuing his stake at nearly $2 billion today.

The Chewy cofounder and activist investor first revealed a position in the video-game retailer a year ago, and grew his holding to just over 9 million shares by mid-December. He spent a total of $76 million to build that position, regulatory filings show, indicating he paid an average price of $8.40 a share.

GameStop's stock price has ballooned since then, valuing Cohen's 12.5% stake at $1.9 billion today - an almost 25-fold gain on paper. The company's shares have soared more than 1,000% this year alone, from below $20 at the start of January to about $210 at the time of writing.

Cohen is both a major beneficiary and key driver of the stock surge. The billionaire e-commerce entrepreneur's investment was a vote of confidence in GameStop last year, and he hinted at his plans to turn the retailer into a technology company in a letter to its board of directors last November.

Since then, he's overhauled the board, secured the role of chairman, and expressed his commitment to transforming the business and helping it realize its potential.

Moreover, Cohen's activism was a key reason why retail investors decided to execute a short squeeze on GameStop shares in January, boosting its price as high as $483 - briefly valuing the RC Ventures chief's stake at $4.3 billion. Cohen's involvement may also have shored up GameStop's stock price when the company issued 8.5 million new shares earlier this year, raising $1.7 billion.