Jack Dorsey was named as the chief executive officer of Twitter, while maintaining the same position with Square, an arrangement that raised eyebrows.

In a SEC filing, Twitter said Dorsey would upgrade from interim CEO to take the job permanently. Some observers have questioned whether he can hold down both Twitter and Square jobs, particularly as the latter eyes a high-profile IPO.

Dorsey will lose one role, agreeing to step down as Twitter’s chairman.

However, there are no plans for him to receive “direct compensation” for the CEO role at Twitter.

Dorsey has been serving as the company’s interim CEO since July this year, having previously held the post of president and CEO from May 2007 until October 2008.

Since February 2009, Dorsey has been full-time CEO of Square, the mobile payments firm he co-founded and which is now close to announcing plans for an IPO.

For good measure, he also serves on the board of directors of The Walt Disney Company.

“Mr Dorsey was selected to serve on the Board because of the perspective and experience he brings as one of Twitter’s founders and as one of Twitter’s largest stockholders, as well as his extensive experience with technology companies,” the filing said.

The board also appointed Adam Bain as chief operating officer. Bain’s previous post was as Twitter’s president, global revenue and partnerships. He had worked for eleven years at News Corporation before joining Twitter.