In an interview with NPR, the chairman of the Securities and Exchange Commission said he was aiming to unveil tougher rules for a hot investment crazed called SPACs by early next year.

Regulators including the SEC are investigating a planned merger between a shell company and former President Donald Trump's social media startup.

Special purpose acquisition companies, or SPACs, are exploding in popularity. They allow companies to go public without all the hoops of an initial public offering.