to the National Abortion Federation. It has also funded the Guttmacher Institute, which tracks demographic and legislative trends, and Gynuity Health Projects, which focuses on medication abortion. Gates Foundation Warren Buffett's intention was originally to leave 99% of his estate to the Buffett Foundation, but in June 2006 he announced that he would give 85% of his wealth to the Bill & Melinda Gates Foundation instead. Buffett stated that he changed his mind because he has grown to admire Gates's foundation over the years; he believed that the Gates Foundation would be able to use his money effectively because it was already scaled-up. "Susan's Foundation" is to receive a bequest of about $3 billion over a span of many years. Source of wealth The vast bulk of Buffett's wealth consists of his personal holdings in Berkshire Hathaway, a conglomerate of which he controls almost 40% directly, and which he has managed personally since the mid-1960s. Giving away such a large part of his company holding could prove problematic in that much of the business of Berkshire Hathaway consists of stock-issuing insurance companies, such as GEICO and General Re. In the past, many state insurance regulators have had serious concerns about allowing for-profit insurance companies – as opposed to mutual insurance companies – to be ultimately controlled by non-profit entities. In a famous case regarding this, the MacArthur Foundation was forced to divest itself of Bankers Life and Accident. Notes External links Buffett family Medical and health foundations in the United States Berkshire Hathaway