Which document is NOT considered valid for vehicle registration?

In the context of vehicle registration in Pennsylvania, there are specific documents that are typically required to complete the process successfully. While proof of insurance is an essential document for operating a vehicle legally, it is not specifically required for the registration process itself.

The accepted documents like a valid registration, PENNDOT card, and title certificate directly validate ownership and allow for the vehicle to be officially registered with the state. The valid registration confirms that the vehicle has already been registered, the PENNDOT card serves as proof of the vehicle's registration details, and the title certificate provides evidence of ownership.

On the other hand, while proof of insurance is necessary for legal driving and can sometimes be a prerequisite for registration to ensure that the vehicle is insured when it’s registered, it is not classified as one of the primary documents for vehicle registration. Therefore, it does not meet the criteria of being a direct form of proof for registration purposes, making it the correct choice for the document that is not considered valid for vehicle registration.