Microsoft co-founder Bill Gates exits company's board of directors

Microsoft on Friday announced that co-founder Bill Gates has left its board of directors to devote more time to philanthropy.

The 64-year-old stopped being involved in day-to-day operations at the firm more than a decade ago, turning his attention to the foundation named after him and his wife, Melinda.

Gates served as chairman of Microsoft's board of directors until early in 2014 and has now stepped away entirely, according to the Redmond-based technology giant.

"It's been a tremendous honor and privilege to have worked with and learned from Bill over the years," Microsoft chief executive and company veteran Satya Nadella said in a release.

"Bill founded our company with a belief in the democratizing force of software and a passion to solve society's most pressing challenges; and Microsoft and the world are better for it."

Nadella added that Microsoft will continue to benefit from Gates' "technical passion and advice" in his continuing role as a technical advisor.

"I am grateful for Bill's friendship and look forward to continuing to work alongside him," Nadella said.

Regularly listed among the world's richest people, Gates was a geeky-looking young man when he and Paul Allen co-founded Microsoft in 1975. Gates left his CEO position in 2000, handing the company reins to Steve Ballmer to devote more time to his charitable foundation.

He gave up the role of chairman at the same time Nadella became Microsoft's third CEO in 2014.