Twitter co-founder Biz Stone is back at the company

Twitter co-founder Biz Stone announced on Tuesday that he is returning to the company he left in 2011. “My top focus will be to guide the company culture, that energy, that feeling,” he wrote in a blog 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,” he added.

Excited to have Biz's energy and heart back at Twitter! #BizIsBack https://t.co/7Cc0snAP2c

— jack (@jack) May 16, 2017

Stone left Twitter in 2011 to co-found online publishing platform Medium and search engine company Jelly, which was sold to Pinterest in March this year. "The (Pinterest) deal did not require me to work at the company we sold to, but I'm the type of person who has to keep working," Stone said.

Stone is returning to Twitter when the micro-blogging site is trying all it can to drive growth both in terms of user base and revenues. Last month, Twitter posted its strongest growth in monthly users since early 2015. The average monthly active users increased 6 percent to 328 million in the first quarter of 2017 from a year earlier.

Market too responded positively on the development as Twitter shares were up 2.4 percent at $19.65.