A “bobtail” truck is one that travels from one point to another without a trailer in tow, typically when a driver is under dispatch. So, for instance, when a driver is dropping a trailer at Point A, then traveling to Point B (without a trailer attached) to pick up another trailer, he is covered by Bobtail Insurance while between points.
The term “Bobtail Insurance” is sometimes used in tandem with “Non-Trucking Use Liability Insurance, or NTLI. This is the type of coverage provided to an owner operator when he is not under dispatch to the motor carrier. In the event of an accident or damage, the NTLI would respond to the claim rather than the driver's primary auto liability insurance.