Zipcar plans an IPO

Zipcar Inc., whose backers include Steve Case’s Revolution LLC, plans to go public, the Washington Business Journal reports.

The Cambridge, Mass.-based company has filed with the Securities and Exchange Commission for an initial public stock offering, though the company has not set a share price or number of shares to be sold. It has not set a date for the offering either.

Zipcar, which rents cars by the hour or by the day, has a big presence in the Washington metro area. Its cars are available in about 50 cities and on more than 100 university campuses.

Flexcar, a Zipcar competitor owned by Case’s Revolution LLC, merged with Zipcar in 2007.