Steve Ballmer, former CEO of Microsoft, announced through an open letter that he is leaving the company's board of directors, IGN reported.

The letter was addressed to his replacement, CEO Satya Nadella. The open letter along with Nadella's response was posted on Microsoft's website. Nadella took over Ballmer's position six months after the latter announced his retirement from the company.

"As I approach the six month mark of my retirement and your appointment as CEO, I have been reflecting on my life, my ongoing ownership of Microsoft stock, and my involvement with the company," Ballmer wrote to Nadella.

"I have reached some conclusions and wanted to share them with you," he continued. "I know August is the key month during which the company starts to prepare the proxy statement for the next shareholders' meeting, and so these thoughts are probably timely for that too."

Ballmer advised his successor to keep steering the company towards an innovative path through technological developments. Doing so will ensure the company's high-status in the world's growing tech industry, according to the Wall Street Journal.

"Microsoft will need to be bold and make big bets to succeed in this new environment," he wrote. "Writing great software is a tremendous accomplishment and selling software has been a fabulous business."

"Our board must also support and encourage that fearlessness for shareholders to get the best performance from Microsoft," he added. "You must drive that."

Nadella responded and told Ballmer that through his leadership, Microsoft has grown into a true tech giant. He also assured his former mentor that the company is in good hands.

"Thank you for all of your support during my transition this year and for the past 34 years," Nadella replied. "It's been a great privilege to have worked with you and learned from you."

"Under your leadership, we created an incredible foundation that we continue to build on - and Microsoft will thrive in the mobile-first, cloud-first world," he continued.

Ballmer joined the company in 1980 and was appointed as Microsoft's CEO in 2000. As one of his key contributions to the company, Ballmer served as the driving force behind Microsoft to enter the game console industry with the introduction of the first Xbox in 2001.  

The former executive explained that his decision to step down from his position will give him more time to focus on his civic duties, teaching commitments and ownership of the Los Angeles Clippers, Bloomberg reported.