By Carlo Versano

Lyft filed for its initial public offering in a confidential registration statement with the Securities and Exchange Commission, it announced in a press release Thursday morning.

The ride-hailing company said it has not yet determined the number of shares or price range for the IPO.

The company's statement is the first official step in becoming a public company. Lyft had previously lined up the banks, reportedly JPMorgan and Jeffries, that will do the deal. It now must wait for the SEC to complete its review before it can initiate the offering. The company was most recently valued around $15 billion, and a successful float could raise that number.

The IPO is expected to commence in the first half of 2019. Rival Uber also has an IPO in the works, which is sure to eclipse Lyft's valuation when it is priced. Uber has been speculated to be worth as much as $120 billion.

For Lyft, "there's a lot of advantages to going first" said Maya Kosoff of Vanity Fair.

Lyft is closer to profitability than Uber (though neither is there yet), benefits from better PR, and any regulatory changes that stem from Lyft's rollout could affect Uber's valuation, Kosoff noted.

Lyft, which only operates in North America, has sought to diversify from ride-hailing, and recently acquired Motivate, the country's largest bike-share operator. It is also piloting electric scooters in select markets. Uber has made similar moves, though both companies get the lion's share of their revenues from the commissions generated from the car rides users book on their apps.