Bill and Melinda Gates, two of the richest people in the world who were reshaping philanthropy and public health with the fortune made by Mr. Gates as co-founder of Microsoft, said on Monday they were divorcing.

For decades, Mr. and Mrs. Gates have been powerful forces on the world stage. Their enormous charitable donations give them access to the highest levels of government, business, and the non-profit sector. The Bill and Melinda Gates Foundation, with approximately $ 50 billion in endowment, has made a tremendous impact in areas such as global health and early childhood education, and has made great strides in reducing deaths from malaria and other infectious diseases. Last year, the couple were particularly visible and regularly commented on the global battle against Covid-19 when their foundation spent more than $ 1 billion fighting the pandemic.

“After much thought and work on our relationship, we made the decision to end our marriage,” said Mr. and Mrs. Gates in a statement posted on Twitter.

They went on to say that they “have built a foundation that works around the world to help all people live healthy and productive lives” and that they “continue to believe in this mission” but “can no longer believe us” in grow together as a couple in this next phase of our life “

The foundation said in a statement that Mr. and Mrs. Gates would remain co-chairs and trustees and that no changes were expected in the organization.

“They will continue to work together to develop and approve foundation strategies, advocate for the foundation’s problems, and set the general direction of the organization,” the statement said.

Even so, the divorce will raise new questions about the fate of Gates’ fortune, much of which have not yet been donated to the Gates Foundation. The 65-year-old Gates, co-founder of Microsoft, is one of the richest people in the world with an estimated value of $ 124 billion, according to Forbes. The Gateses have been married for 27 years and have three children aged 18-25.

“The Gates Foundation is now the most important and influential philanthropic entity in the world,” said Rob Reich, professor of political science at Stanford University. “Divorce can have a huge impact on the Foundation and its work around the world.”

With 1,600 employees in offices around the world, the Gates Foundation awards approximately $ 5 billion each year in areas such as global public health and development. In more than two decades, the foundation has spent billions bringing vaccines to developing countries and worked with pharmaceutical executives to transform the market.

The foundation used their expertise and relationships to play a key role in formulating the global response to the pandemic, investing early in vaccine candidates, and Covax, the global initiative to organize the purchase of vaccines for 92 poor countries and dozens of other nations to help shape.

Mr. and Mrs. Gates have received high praise for their efforts, but the Foundation has also received a lot of criticism for protecting the intellectual property rights of private companies. This has come into focus more than ever as many national governments have pushed for open access to Covid vaccines to end the pandemic.

“Bill and Melinda Gates pioneered the great philanthropy of today,” said David Callahan, founder of Inside Philanthropy. “Everything was oversized.”

A former employee who worked with both gates said that after hearing the news, staff in orbit the foundation texted and emailed each other to find out what had happened and what it could mean for the foundation. The consensus was that it would be fine for now, the former employee said, but there were questions about how that would affect – depending on how amicable the divorce is and how they work together in the future – when it comes next time comes to review strategies and future plans.

“While this is obviously a difficult time of personal change for our co-chairs, they have jointly assured me of their continued commitment to the foundation that they have worked so hard over the past 20 years to build together,” said the managing director of Foundation, endowment. Mark Suzman shared an email with staff on Monday.

He described “making some last-minute adjustments to their schedules,” but said both would continue to attend meetings inside and outside the foundation and speak directly to staff at the upcoming annual staff meeting.

While the Gateses did not provide details on how they would structure their finances, it is believed that they have a marriage agreement. The Gateses are the largest farmland owners in America and have massive investments through Cascade Investment, which manages the personal fortune of Mr. Gates and owns large stakes in the Four Seasons hotel chain, the Canadian National Railway, and AutoNation, the largest car dealership chain in the country among other companies. The family’s homes and land include a 66,000-square-foot mansion in Washington state, which has amenities like a trampoline room, screening room, and a multi-room library filled with rare documents and artifacts.

Mr. Callahan said Ms. Gates, 56, could become even more influential in the years to come.

She already has her own company, Pivotal Ventures, which she has invested in to invest in women’s economic empowerment issues. (Mr. Gates has his own private office, Gates Ventures, to pursue interests outside the foundation.) Should she receive any of the Microsoft stakes from Mr. Gates, she could start a new foundation or give direct gifts to others she sponsors Purposes.

“You could imagine Melinda Gates being a much more progressive giver herself,” said Mr. Callahan. “She will be an important force in philanthropy for decades to come.”

In 2019, Amazon founder Jeff Bezos and longtime wife MacKenzie Scott divorced. Ms. Scott received $ 36 billion worth of Amazon stock at the time and immediately set out to make billions of dollars in direct grants to a variety of progressive organizations.

Mr. Gates recently resigned from some of his business activities. Last year he left the board of directors of Microsoft and the board of Berkshire Hathaway, the conglomerate of his close friend Warren Buffett.

Mr. Buffett has donated billions of dollars to the Gates Foundation over the years and has pledged to leave most of his fortune to the foundation when he dies. In 2010, Mr. Buffett and the Gateses founded the Giving Pledge to encourage wealthy individuals to donate much of their money to charity.

Mr. and Mrs. Gates have had relationship problems in recent years, said two people close to them. There have been multiple times when the relationship was nearing breakdown, but they worked to keep it together, people said. Mr Gates decided to partially step down from the boards of Microsoft and Berkshire Hathaway to spend more time with his family, these people said.

“When he struggled to make the decision to get married, it was incredibly clear to him that it wasn’t about me, but about ‘Can I strike the right balance between work and family?'” Ms. Gates said in an interview in 2019 in the Sunday Times of London. “And believe me, I can remember a few days that were so incredibly difficult in our marriage when you thought, ‘Can I do this?'”

Karen Weise contributed to the coverage.