Uber says CFO Brent Callinicos is leaving after 18 months to spend more time with his family

Ride-sharing company Uber said Monday that CFO Brent Callinicos is leaving the company to spend more time with his family.

Uber said Gautam Gupta, its head of strategic finance, will be in charge of its finance while it looks for a permanent replacement. It said Callinicos will continue to advise Uber.

The San Francisco company announced Callinicos' departure in an email from CEO Travis Kalanick.

In an email to Uber employees, Callinicos said he has worked nonstop since receiving his MBA 26 years ago and wants to spend more time with his wife and daughter. Uber hired Callinicos in September 2013. He worked at Google Inc. for seven years and was treasurer and chief accountant before joining Uber. He also worked for Microsoft Corp. for 14 years.

Uber is a taxi alternative company that lets passengers summon cars through an app, linking would-be riders directly to nearby drivers. It operates in more than 50 countries and is valued at $40 billion. However it faces a variety of legal and regulatory challenges as it expands.

The company has been criticized over the thoroughness of its background checks on drivers and other safety issues as well as its method of raising prices when demand goes up.