Dara Kerr: “California regulators have sent warning letters to Uber, Lyft and Sidecar to say that their new carpool features are illegal. Sidecar revealed Thursday that it received the letter from the California Public Utilities Commission, which said the ride-sharing service was breaking the law by testing its new Shared Rides, or carpool, feature. A Lyft spokesperson told CNET that it too received a similar letter. Initially, Uber told CNET that it didn’t get the letter but now the company says it was indeed contacted by the CPUC. The CPUC also confirmed with CNET that it sent two copies of the letter to Uber — one to company CEO Travis Kalanick and one to Chairman Garrett Camp — on September 8.”