The largest IPOs in history so far: Saudi Aramco Alibaba SoftBank Agricultural Bank of China VISA Industrial and Commercial Bank of China Now, SpaceX is expected to raise up to $75 billion in its IPO, which could debut as early as June 12. This is 2.5 times the size of Saudi Aramco's IPO, which is currently the largest IPO in history. SpaceX going public will likely push Musk's wealth to another level.