Originally Published: 23 MAR 22 14:43 ET

By Jennifer Korn, CNN Business

(CNN) -- Mackenzie Scott said Wednesday she has donated more than $3.8 billion to 465 organizations since June.

In a Medium post, Scott said her team's focus in the past nine months continued to be helping underrepresented people from various backgrounds and communities. The billionaire philanthropist gave money to Planned Parenthood locations across the United States as well as to organizations helping at-risk children, minorities, refugees and rural health access, according to the post.

Scott, the ex-wife of Amazon founder Jeff Bezos, recently gave $436 million to Habitat for Humanity — her largest known donation to date — and $133.5 million to educational nonprofit Communities in School, according to previous statements from the organizations.

"When our giving team focuses on any system in which people are struggling, we don't assume that we, or any other single group, can know how to fix it. We don't advocate for particular policies or reforms," Scott wrote. "Instead, we seek a portfolio of organizations that supports the ability of all people to participate in solutions. This means a focus on the needs of those whose voices have been underrepresented."

With an estimated net worth of $55 billion according to the Bloomberg Billionaires Index, Scott is well known for her philanthropic behaviors and surprise donations to organizations. Scott signed the Giving Pledge in 2019, a non-binding agreement launched in 2010 by Warren Buffett and Bill and Melinda Gates for billionaires to promise to give away their wealth to those in need.

Scott has thus far given away over $12 billion of her personal wealth in four rounds, according to Forbes.