I know that I cannot use real car models in a game without permission. However, I am interested in a classic (vintage) cars from era before 1950. Some of the companies no longer exist, or were bought by some other company and this by some other company etc. Some cars had custom-made chasis on top of a "skelet".
How is licensing for those cases? Same as for "today" cars, or is there any exception? Something like books where from certain date there are no longer copyrights.