'Forbes' reports that Musk's net worth went from $320 billion in 2021 to $138 billion in January 2023. Plummeting Tesla shares accounted for much of the drop. Those shares fell even more after Musk acquired Twitter for $44 billion. Those shares fell even more after Musk acquired Twitter for $44 billion. According to the Guinness World Records, the $182 billion to $200 billion Musk lost is the "largest loss of personal fortune in history". Softbank founder and CEO Masayoshi Son previously held the record for losing $58.6 billion in 2000.