Sorry I didn't kill it earlier.
I usually go by a number of factors to identify spam (by a bot or a person).
- Replying to an old topic.
- Level of new contribution to the topic.
- Fewer than 5 posts (usually only 1).
- Links in the signature or post that are unrelated to IP, law, or innovation.
If the poster has only 1 post, I'll delete the post and not ban the poster. If they have more than 1 post, I'll read the rest and see if they're spam or legit. If spam, I'll ban the user. If legit, I'm more likely to leave all posts.
A lot of spammers fake contributions by copying and pasting earlier posts in the topic, so it can seem really on topic.
Regards.