A more thorough explanation:

The last-employer rule is a legal doctrine that determines which employer is responsible for compensating a worker who has suffered an occupational injury or illness. According to this rule, the employer that exposed the worker to the harmful substance or condition just before the onset of the injury or illness is liable for the damages.

For example, suppose a worker has been exposed to asbestos while working for several employers over the years. If the worker develops mesothelioma, a type of cancer caused by asbestos exposure, the last employer that exposed the worker to asbestos will be held responsible for compensating the worker for medical expenses, lost wages, and other damages.

Another example could be a worker who develops carpal tunnel syndrome from repetitive motions while working for different employers. The last employer that exposed the worker to the repetitive motions will be held responsible for compensating the worker for the injury.

The last-employer rule is designed to simplify the process of determining liability for occupational injuries or illnesses. It ensures that the employer that caused the injury or illness is held responsible for compensating the worker, rather than requiring the worker to identify which employer was responsible for the initial exposure.