General Motors Co. filed paperwork Thursday that would open the door to an initial public offering, marking one of the first steps necessary for the U.S. government to reduce its 60.8 percent ownership stake in the company.

The "new GM" does not have any publicy traded securities. The number of shares the company may offer, and their price, have not yet been determined.

In addition to owning a majority of GM's common stock, the Treasury Department holds $2.1 billion of the automaker's Series A preferred stock. The Series A stock is not included in the IPO. Right now, it's unclear how much of its common stock Treasury would offer.