The four nonprofits managed by billionaire businessman Warren Buffett received more than $750 million in Berkshire Hathaway stock, but unlike his yearly donations to charity each summer, the Bill & Melinda Gates Foundation was not among the recipients.

Since announcing a plan to donate his fortune over time in 2006, Buffett has given annually to the same five charities, with the Gates Foundation getting the largest donations. The 92-year-contributions old's on Wednesday are the first time she has given a second significant gift in the same year.

According to a filing with the Securities and Exchange Commission, Buffett handed the Susan Thompson Buffett Foundation—named for his first wife—1.5 million Class B shares in the Omaha, Nebraska-based conglomerate he oversees. Additionally, he granted 300,000 Class B shares to each of the Sherwood, Howard G. Buffett, and NoVo foundations, which are all controlled by his children.

He provided 1.1 million Class B shares to the Susan Thompson Buffett Foundation, 11 million Class B shares to the Gates Foundation, and 770,218 shares to each of his children's three charities in June.

The fresh donations this week's motivation wasn't immediately obvious, and Buffett didn't immediately react to inquiries about them on Wednesday. Questions were not immediately answered by the Buffett family foundation or the Gates Foundation, which both received the grants.

Buffett upped the amount pledged to the foundations his children oversee ten years ago because he was happy with what they had done with his money. This was the only other big change he made to his giving plans throughout the years.

Although the Susan Thompson Buffett Foundation keeps a low profile, it has consistently contributed significantly to organisations like Planned Parenthood and others in support of abortion rights throughout the years. Since the US Supreme Court reversed Roe v. Wade earlier this year, Buffett has not disclosed any changes to his philanthropic intentions.

Susie Buffett, 69, uses her Sherwood Foundation to advance early childhood education and fund numerous initiatives in and around Omaha, where she was born and raised. With his name-brand foundation, Howard Buffett, 67, is aiming to solve world hunger while assisting farmers in developing countries increase their output. In order to end violence against women, Peter Buffett, 64, has committed his NoVo Foundation to empowering women and girls around the world via education, collaboration, and economic development.

Buffett still has more than 31% of the voting power at Berkshire even after these most recent contributions. The eclectic conglomerate Berkshire Hathaway is the owner of over 90 businesses, including the BNSF railroad, Geico insurance, many significant utilities, and a variety of manufacturing and retail businesses like Precision Castparts, Dairy Queen, and Helzberg Diamonds. Along with the businesses it owns entirely, Berkshire also holds significant stakes in firms like Apple, Bank of America, Coca-Cola, and others.