A private foundation is a charitable organization that, while serving a good cause, might or might not qualify as a public charity by government standards. The Bill & Melinda Gates Foundation is the largest private foundation in the U.S. with over $38 billion in assets. Most private foundations are much smaller. Out of the 84,000 private foundations that filed with the IRS in 2008, Approximately 66% have less than $1 million in assets, and 93% have less than $10 million in assets. In aggregate, private foundations in the U.S. control over $628 billion in assets and made more than $44 billion in charitable contributions in 2007.