As I understand it, problem wasn't Universal. It was that the publisher didn't put his name on the copyright page, so the art became public domain under the laws at the time.
That law has been replaced and you now get copyright automatically.
That law has been replaced and you now get copyright automatically.
Sounds like you could accidentally make someone else's art public domain by forgetting to include them on the copyright page...
edit well, perhaps that's part of the reason the copyright laws were updated.