SAN FRANCISCO • Mr Bill Gates is stepping down from the board of Microsoft, the software giant he helped found more than four decades ago.
Mr Gates said on Friday that he would also step down from the board of Berkshire Hathaway, the conglomerate run by his close friend, Mr Warren Buffett.
"I have made the decision to step down from both of the public boards on which I serve - Microsoft and Berkshire Hathaway - to dedicate more time to philanthropic priorities including global health and development, education, and my increasing engagement in tackling climate change," Mr Gates wrote in a LinkedIn post.
For decades, Mr Gates was the face of Microsoft. Known for his technical acumen and ruthless business practices, he helped to establish Microsoft's Windows as the primary system for the PC.
Microsoft said that he would remain a technical adviser to the firm.
Mr Gates has been stepping back from Microsoft in recent years.
He left his day-to-day role at the company in 2008 and served as the board's chairman until 2014.
The firm said that he wants to devote more of his time to his philanthropy at the Bill & Melinda Gates Foundation, one of the world's biggest non-profit organisations, which was started with the billions of dollars he made from Microsoft.
He remains one of Microsoft's biggest individual shareholders.
As of December, he held more than 100 million Microsoft shares, roughly 1.3 per cent of the company's shares. His stock is worth about US$16 billion (S$23 billion).
He said he would remain active at the firm and would work closely with chief executive Satya Nadella.
Mr Gates wrote: "Microsoft will always be an important part of my life's work... I feel more optimistic than ever about the progress the company is making."
In his post-Microsoft career, Mr Gates has become better known for his work in fighting infectious diseases and climate change.
Last month, the Gates Foundation said it would commit an additional US$100 million to fight the coronavirus. The organisation pledged US$10 million earlier in the year.
He has persuaded Mr Buffett, his bridge partner and neighbour on the list of the world's richest people, to donate most of his fortune to the Gates Foundation.
Mr Gates joined the Berkshire Hathaway board in 2004.
The conglomerate has nominated Mr Kenneth Chenault, the former chief executive of American Express, to replace Mr Gates on the board.
Mr Daniel Ives, managing director of equity research at Wedbush Securities, said in a research note that Mr Gates stepping down from the Microsoft board was not a surprise and that it was a vote of confidence for Mr Nadella and the direction of the company.
Mr Gates founded Microsoft in 1975, dropping out of Harvard University and joining Mr Paul Allen, his friend and technology collaborator.
In 1975, they moved to Albuquerque where fledgling microcomputer firm Mits made the Altair 8800, a primitive machine often credited as the first PC.
Microsoft's first product was a version of the Basic programming language that could run on the Altair.
That was the start. Later, after Mr Gates moved Microsoft to Seattle, a succession of highly successful commercial products followed.
By the mid-1990s, Microsoft was the dominant personal computer software company.