Stable investment vehicle I am not so sure. I think an index fund or even gold will outperform it over 100 years. Superman comics rely on people giving a shit about superman which will fade over time. Superman isnt a big thing for gen z for example.

Who knows, but some comic books characters like Batman and Spider-man are bigger that ever, while others like Tarzan is losing relevance.

> they ain’t making more of them.

I always wonder exactly how difficult it would be to get the paper, ink, staples, etc exactly right. I'm sure it would be difficult but 9m is a big payoff if you can.

I assume the content isn't as important as the fact the object itself is the original. Original paper, original ink, original release date. The object itself comes from the original factory, survived through time etc. I would expect some tests will verify it uses the correct paper, has the signs of age, etc.

Even if you could duplicate it down to the molecule I would assume it wouldn't hold the same value since it doesn't have the same history. Assuming you'd want to sell it in good faith as a replica.

If you’re going to get into forgery of historical memorabilia there’s probably easier targets than Superman comic books, no?