Until 2012, Sprint was the main MNO partner for the major US cable operators, and had worked with them on MVNO deals, joint spectrum ownership and WiMAX investments. In that year, however, Verizon lured Comcast, Time Warner Cable, Cox and Brighthouse (now, after various acquisitions, consolidated as Comcast, Charter and Cox) to its own side. It acquired many of their spectrum assets and agreed an MVNO and cross-marketing alliance. The latter was dumped the following year, perhaps as Verizon realized how dangerous a threat cable could be to its own 4G plans, but the MVNO agreements have persisted and were recently renewed and extended with Comcast and Charter (though Cox is reported to be in talks with AT&T). This is…