Comcast (NSDQ: CMCSA), Time Warner (NYSE: TWX) Cable and Cox Communications have pulled out of the Pivot joint venture with Sprint (NYSE: S) (the fourth cable partner, Advance/Newhouse Communications, declined to comment), and the cable companies have stopped marketing the Pivot service and in the next few weeks will give their customers on Pivot the option of switching to a traditional Sprint plan, confirms AP, following a rash of reports. Customers will be able to keep their phones and numbers and receive a month’s free Sprint service—since I’m sure Sprint would like the customers. The four cable partners invested $100 million and Sprint invested $100 million in the venture, launched a year ago at CTIA. Back in November Time Warner said demand for Pivot was tepid, but it had no plans to end the service. Today the cable companies said the complexity of the offering “made marketing Pivot a chore and controlling the direction of the joint venture difficult”.

The AP article notes that Sprint is still a partner in SpectrumCo, but last August the telco said it was pulling out of the JV.

GigaOM reports that Comcast “is creating its own wireless division and has hired the former CTO of Telefonica (NYSE: TEF) O2 Europe, Dave Williams, as the unit’s CTO”, although Comcast hasn’t confirmed the report. The suggestion is that mobile services could be offered over a national WiMax network the cable company is rumored to be talking with Sprint about. If worse comes to worse there is always Verizon’s (NYSE: VZ) promised open network.

• Comcast & Time Warner Talking To Clearwire & Sprint on National WiMax Network