[datax2]

As others have pointed out VIN as your primary level of detail is fairly flawed. You should also be filtering on vehicle registrations. A possible scenario here is someone owns their car, gets into an accident, repairs it or sells it off (insurance sell off). Someone else buys it gets difference insurance, and has an accident because its a new car to them. You would never know this vehicle story without integrating the registration history or at least buy and sell dates to know it has exchanged hands.

Yes Fraud is tricky, but a VIN does not equal a person (PII) committing the behavior, and these poor association attempts leave innocent people screwed by insurance companies. What makes this bad analysis annoying, is the constant caveats, if you know VIN associations don't prove fraud then maybe don't build some sort of risk scoring on it, and then try an sell it.