6. Jon Hunstman Sr., U.S.

Donations: $1.25 billion

Net Worth: $925 million

Born in 1937, he is an American businessman and philanthropist. He is the founder of Huntsman Corporation. In 1992 he was diagnosed with prostate cancer and on the way to the hospital for treatment, he made three stops: First the chemicals mogul dropped by a homeless shelter and left a $1 million check. Then he stopped at a soup kitchen and handed over another $1 million check. Finally he dropped off $500,000 at the clinic that had found his disease. Since then Huntsman says he plans to give it all away before he dies and has donated the majority of his fortune to his cancer foundation.

7. Dietmar Hopp, Germany

Donations: $1.25 billion

Net worth: $5.5 billion

Born in 1940, he is a German software entrepreneur. He was one of the founders of SAP AG in 1972. In 1995 he donated 70% of his SAP assets to fund the nonprofit Dietmar Hopp Foundation which is now one of Germany's and Europe's largest private foundations. Its focus is regional supporting youth sports, cancer research and healing diseases in children in particular.

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