An thought experiment shows that if Bill Gates had never sold Microsoft stock since 1999, his net worth would today exceed one trillion dollars. He initially held about 1 billion shares, and with stock splits, his ownership stake would have increased significantly, potentially far surpassing Elon Musk. However, he systematically sold shares to fund the Gates Foundation, ultimately reducing his stake to about 1.3%, exchanging unimaginable personal wealth for decades of significant impact on global philanthropy.