@Cain 24 June 2020 more from that month

Need a little help with moderation. When I see a post with the EXC tag, I know that means it's exclusive but does that mean it's simply not in any other communities? Is the non-OC tag no longer being used? Basically, how do I know if large parts of an article were mostly copied from the internet? I got a submission that didn't have the EXC tag but wasn't sure if that was just because they had submitted to multiple read.cash communities, but when I did a quick search, I saw most of the article was copied from a Medium post. Requesting some clarification. Thanks!