In an excerpt from Walter Isaacson's biography of Elon Musk, Bill Gates thought Elon Musk became 'super mean' after finding out Gates shorted Tesla stock in early 2022. When Gates followed up with Musk again in April 2022 to discuss philanthropy, Musk shot back that he could not take Gates' climate philanthropy seriously since Gates had a $500 million short position against Tesla. Gates said he took the short position as a business decision, expecting that electric vehicle supply would soon outpace demand. Gates and Musk were two of the biggest philanthropic donors in 2022, with Gates donating $5 billion and Musk donating $1.9 billion.