Microsoft is witnessing the biggest reshuffle of its top rank executives under the new CEO Satya Nadella, with Mark Penn, mastermind of the "Scroogled" campaign, becoming the company's chief strategy officer.

Some of Microsoft's high-ranking officials are either moving within the company or bidding farewell. This is the first biggest shuffle of top Microsoft officials since Satya Nadella took control of the company as the new CEO from Steve Ballmer. The change will see EVP of business development and evangelism Tony Bates and EVP of marketing Tami Reller bow out of the company, while Mark Penn becomes the chief strategy officer, a person briefed on the change told Re/Code.

Penn, who masterminded the "Scroogled" campaign highlighting Google's privacy concerns, was previously supervising Microsoft's advertising and strategy. His new role will require Penn to solely focus on new markets for Microsoft for and where to make further investments. Other changes include Bates' departure from Microsoft. He served as the company's VP of business development.

Bates joined Microsoft in 2011 after the company acquired Skype services. He is among the senior members at the company and was a potential candidate to replace Ballmer, the former CEO. Bates will leave the company immediately, but there are no details about his future plans.

Another top-rank official, Reller, will bid farewell to the software company. She was with Microsoft since 2001 and has experience in handling the company's flagship unit as CMO and CFO. Reller became a part of Microsoft after the acquisition of Great Plains Software where she was an active executive since her college days in 1984, the report said. Sources also revealed that Reller will stick around to help with the transition.

To fill the gaps, sources added, EVP of advanced strategy, Rudder, will temporarily undertake Bates' duties, while Microsoft's marketing executive Chris Capossela will take Reller's palce. Capossela will also oversee the advertising as Penn is assigned to manage the company's strategy.

The change of positions is still unofficial but the information was shared by Nadella with the top staff, Friday. The official public announcement is expected to happen Tuesday.