I have a dirty trick to ignore "bots" recruiters in Linkedin:
I just put a greek character on my name or add an emoticon, so I got a lot of messages starting with:
"Dear name ..
So, it's safe to ignore the message. Even when probably I'm not interested I used to reply with a template message, but I won't waste 30 seconds with a bot.
I can see very similar movements this robot is doing compared to my old robot. I really like the screen outputs of it.