Seattle software boss and model driver Kenn Dahl was gobsmacked by a whopping 21 per cent hike in his car insurance. After an investigation, he found that it was due to a sneaky snitch embedded in his Chevrolet Bolt.

Dahl, 65, obtained a 258-page dossier from LexisNexis, the New York data giant with its tentacles in the auto insurance pie. This 'consumer disclosure report,' a legal obligation under the Fair Credit Reporting Act, laid bare over six months of Dahl's driving life—640 trips, to be exact—tracking every hard stop and speedy start without so much as a by-your-leave.

General Motors, the creators of his trusty Bolt, have been feeding his driving data to LexisNexis. The firm's spokesman, Dean Carney, defends the move, claiming it's all about tailoring insurance to the individual. But with eight insurers lining up for a peek at Dahl's data, it's clear there's more at play here.

US Drivers are unwittingly signing away their privacy on the dotted line of murky contracts and fine print. A Ford patent application explains how carmakers are hoovering up data from internet-connected vehicles and passing it on to the insurance industry.

While some drivers knowingly opt-in for usage-based insurance, others are left in the dark as their cars turn into tattletales. Features like GM's OnStar Smart Driver meant to rate driving habits, are double agents, serving up data to brokers like LexisNexis on a silver platter.

Some GM drivers allege they've been tracked without ever flipping the switch on these features, leading to a nasty surprise when their insurance rates soar.