Ellliott Management, a top activist shareholder firm, disclosed Monday that it has taken a $3.2 billion stake in AT&T.

In a letter to AT&T’s board, Elliott Management partner Jesse Cohn and associate portfolio manager Marc Steinberg wrote that AT&T’s stock could potentially surge to above $60 a share by 2021 if the company “increased strategic focus, improved operational efficiency” and “enhanced leadership and oversight.” That would be a more-than 65% increase from Friday’s closing price of $36.25.

Shares of AT&T soared nearly 10% in premarket trading to around $40 a share. AT&T was not immediately available for comment.

Elliott wants AT&T to divest from many of its non-core businesses, proposing AT&T discuss spinning off DirecTV, its Mexican wireless business, and several other operations. AT&T has purchased several large assets over the years, including its $85 billion purchase of Time Warner, which it completed last year after a lengthy court battle with the US Department of Justice.

AT&T’s media division, now known as WarnerMedia, is CNN’s parent company.

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