A moment of silence, please, for Dan Duncan. The 77-year-old Duncan, a Houston resident, passed away the end of March. He left behind a spouse, four grown children, four grandkids — and a fortune worth $9 billion.
Duncan also left behind another distinction. He has become the first American billionaire to ever leave his heirs a tax-free fortune.
He was a great philanthropist, giving away $250 million to charity over his lifetime.