Bill and Melinda Gates, among the world’s wealthiest couples and most prominent philanthropists, are getting divorced.

In a tweet posted Monday by the Microsoft cofounder, the couple said they will end their marriage of 27 years “after a great deal of thought and a lot of work.”

They added that they would continue to work together at the Bill and Melinda Gates Foundation, which has given away more than $50 billion and is among the world’s largest charitable organizations.

“We continue to share a belief in that mission and will continue our work together at the foundation, but we no longer believe we can grow together as a couple in this next phase of our lives,” they said. “We ask for space and privacy for our family as we begin to navigate this new life.”

A spokesperson for the foundation did not immediately respond to a request for comment.

The pair first began dating in 1987, when Melinda was a Microsoft intern.

According to Forbes magazine, the Gates fortune is estimated to be worth more than $130 billion.

Melinda told the New York Times last year she feels that she has a responsibility to try to better the world in the face of inequity and suffering.

“It’s something I’ve pondered a lot,” she said. “There’s no explanation how you get to be in this situation of privilege. There’s just none.”