[snozolli]

It's a good exercise to try to spot when you're accidentally spreading disinformation.

You might want to ask yourself that very question.

based on some random book from the 90s that was likely also full of bullshit

Nah, it was an excellent book that I pored over.

I don't understand why you guys are so confident with zero basis for your position other than "I'm so used to seeing it that I assume it's legally valid".

As I explained already, "(c)" is gibberish. Go ask a lawyer if you should put meaningless gibberish in the middle of legal disclaimers.

[chungy]

"(c)" as an alternative to "©" predates your 1990s book by many decades. It even predates its common usage on computers (1960s or so), because typewriters have existed since the 19th century and "(c)" has been used since that century and the limitations typewriters imposed on typed documents.

No court will ever be confused by it, your copyright will never be invalidated by it.

[jjk166]

Nope, the comment you're replying to is correct. Look up the Berne Convention.

If your book was actually from the 90s, then it was out of date, as the US adopted the new copyright rules in 1989.