soupglasses, 
This is probably one of the best pages i have read on how to write proper copyright statements in your code. :revblobfoxread:
Explains very well why things like copyright years and year-ranges can be problematic, and why the © is so important as a symbol to use.
Check it out!
https://liferay.dev/blogs/-/blogs/how-and-why-to-properly-write-copyright-statements-in-your-code