One of Uber's key investors, Google may be poised to steal its thunder.

Google is reportedly developing a taxi network to rival Uber.

According to Bloomberg, Google is looking to leverage its extensive research into autonomous cars and its vast stores of traffic data collected via Google Maps to create a system that takes the driver out of the Uber formula.

Google invested more than $250 million in Uber in 2013 and Google executive David Drummond has sat on Uber's board since. Uber board members claim that Drummond has revealed plans for Google to explore its own ride-hailing service.

If Google backs away from its relationship with Uber, the taxi upstart may be forced to partner with an auto manufacturer that has an existing autonomous car development program, but there are few with Google's experience and resources. Uber's existing applications are also based on Google Maps, and if Google decides to withdraw its support, it could leave Uber scrambling to come up with alternatives based on other less-than-ideal mapping and traffic competitors.

Autonomous taxis are not without their own share of hurdles, however, and even if Google delivers on its promise to have self-driing cars on the road in California before the end of 2015, it will take quite some time for a network based on them to achieve the reach Uber currently enjoys.