Biz Stone is rejoining Twitter, and its stock is popping

After almost 6 years away, Biz Stone is rejoining Twitter, the social network that he cofounded - news that sent Twitter stock popping up almost 2.5% at the time of writing.

Stone disclosed the news in a blog post on Medium.

"My top focus will be to guide the company culture, that energy, that feeling," Stone wrote in his post. "I'm not replacing anyone at Twitter. Somebody mentioned I'm just filling the 'Biz shaped hole' I left.

"You might even say the job description includes being Biz Stone."

Back in June 2011, Stone left Twitter, leaving the company without any of its original founders, which also included Evan Williams and Jack Dorsey, on board. His departure followed a tumultuous period of infighting among the trio and Dorsey's ouster as CEO.

Fast forward to 2017: Dorsey has been back in Twitter's CEO seat for two years. Stone recently sold the human-powered search engine Jelly, his latest startup, to Pinterest for an undisclosed sum. And now, with Stone having mended fences with Dorsey, he wrote that he's ready to return to the company he cofounded.

Stone rejoins Twitter at a critical moment for the company. While its service has found itself at the center of global politics, its new user growth has stalled, leaving Wall Street lukewarm on its stock. Still, a recent earnings report painted a rosy picture for the future of the company, even as it moves towards live video to bolster its growth.