Strings of registration attempts. Do I need to worry?

[FoP]

We get regular strings of registration attempts. I've included a pdf of a page just a while ago (it continues a bit on the next page). The IP addresses are all different, locations are from all over the world but I assume they are all done by the same person/bot.

It's very rare that one of them gets through, but what is this and do I need to worry about it?

 

[Paul B]

No, you don't need to worry.