A California smog certificate is only valid for 90 days from the inspection date for title transfer and registration. The smog test results are automatically sent to the DMV via the smog station's smog check machine; so this vehicle's smog test results should already be in the DMV computer system. You can show proof that the vehicle passed the smog test by providing a copy of the smog certificate, but the DMV should already have the test results (certificate number) in the system.