Bill Gates and Melinda French Gates laid out their individual plans for giving away their fortunes almost seven months after announcing their divorce, a move that shook up the world of philanthropy because of the potential impact on their US$50bil foundation.

The couple initially wrote a letter in 2010 for the Giving Pledge, a promise to give away the majority of their money in their lifetime or their wills. On Tuesday, the pledge’s website was updated to include their new separate letters.

Gates said he’ll continue to focus his philanthropy on the Bill and Melinda Gates Foundation’s work. The ex-couple founded the private organisation decades ago and it has since grown into a philanthropic behemoth.

“I’m proud of all we have achieved so far, from supporting the vaccination of more than 800 million children to helping schools keep more kids on the track to graduation,” Gates, 66, wrote in his letter dated Nov 30. “The foundation’s mission has grown over time, but it remains focused on expanding opportunity for the world’s poorest people and improving education in the United States.”

Gates has a net worth of US$136.8bil and French Gates is worth US$11.7bil , according to the Bloomberg Billionaires Index.

In July, months after the couple announced their split and said little would change at the foundation, Gates and French Gates made public major revisions. Along with committing another US$15bil and announcing a plan for new trustees, the pair also said that they may not be able to work together in the future - raising the possibility French Gates will exit.

“If after two years either decides they cannot continue to work together as co-chairs, French Gates will resign her position as co-chair and trustee,” the organisation said in a statement at the time.

In French Gates’s new Giving Pledge letter, she talks about the Gates Foundation, which she helped found, but also her newer philanthropic arm Pivotal Ventures, which is an investment firm mainly focused on gender equality.

“As part of this pledge, I commit to doing more than writing checks,” French Gates, 57, wrote. “I also commit my time, energy and efforts to the work of fighting poverty and advancing equality - for women and girls and other marginalised groups - in the United States and around the world. My giving will continue to focus on the people for whom the barriers to equality are highest.”

 - Bloomberg