Reese Witherspoon's Hello Sunshine to be sold to Blackstone-backed media company for $900 million
A venture backed by Blackstone Group and led by entertainment executives Kevin Mayer and Tom Staggs has agreed to buy a majority stake in Reese Witherspoon's media company Hello Sunshine.

The terms of the deal weren't disclosed, but a person familiar with transaction told CNBC's Julia Boorstin, it was valued at about $900 million.

This is the first acquisition being made by the newly formed company under Mayer and Staggs, who are both former Disney executives. The goal is to build an independent entertainment company for the streaming era. In a battle for subscribers, many streaming services are hungry for new content.

Witherspoon and Hello Sunshine CEO Sarah Harden will continue to oversee its day-to-day operations and will join the yet-to-be-named company's board.

"Our platform will foster a uniquely creator-friendly culture that gives elite talent the resources they need to create and capitalize on their best, most inventive work. We look forward to backing Reese, Sarah, and their world-class team as they continue to produce and identify dynamic, engaging content for years to come," Mayer and Staggs said in a release.

Blackstone will spend $500 million on buying shares of Hello Sunshine from its current investors including AT&T and Emerson Collective, according to The Wall Street Journal, which first reported news of the deal. Witherspoon and some Hello Sunshine executives and investors will retain ownership stakes in the new company.

"Today, we're taking a huge step forward by partnering with Blackstone, which will enable us to tell even more entertaining, impactful and illuminating stories about women's lives globally. I couldn't be more excited about what this means for our future," Witherspoon said in a release.

Hello Sunshine was founded by Witherspoon in 2016 to create content focused on female voices. Its productions include HBO's "Big Little Lies," Hulu's "Little Fires Everywhere" and Apple 's "The Morning Show."

"Kevin and Tom and our partners at Blackstone see what we see – women's stories matter, and we have economic power as consumers, creators and business leaders. Their commitment enables us to double-down on our mission and our ambitious growth agenda," Harden said in a release.

Blackstone Group and Hello Sunshine did not immediately respond to CNBC's request for comment.

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