The couple announced the news in a statement posted to Twitter on Monday, saying that while they plan to continue working together at the Bill & Melinda Gates Foundation, they no longer believe they can continue growing as a couple.

Gates is worth $130.5 billion, according to Forbes. He's one of only eight moguls worth over $100 billion and is currently the fourth richest person in the world.

Most of the reporting of the divorce has focused on how rich Gates is. However, most of the cash the pair have earned is donated to charity through the Bill & Melinda Gates Foundation. They have also pledged to give away most of their fortune through the Giving Pledge, which they launched in 2010.

"Over the last 27 years, we have raised three incredible children and built a foundation that works all over the world to enable all people to lead healthy, productive lives", the couple tweeted.

"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 the next phase of our lives.

"We ask for space and privacy for our family as we begin to navigate this new life."

Melinda, now 56, joined Microsoft as a product manager in 1987, and the two sat together at a business dinner that year in New York.

They began dating, but as Bill told a Netflix documentary: "We cared a lot for each other and there were only two possibilities: either, we were going to break up or we were going to get married."

Melinda said she found Bill - methodical it seems even in matters of the heart - writing a list on a whiteboard with the "pros and the cons of getting married".

They got married in 1994 on the Hawaiian island of Lanai, reportedly hiring all the local helicopters to stop unwanted guests flying over.