What to do about artists who "rip off" or "pass off" your art?

Over the last 20 years of writing this blog I've seen very many examples of artists ripping off other artists (or art societies) - or "passing off" other artists' work as their own - and I've written about this, sometimes at length. (see the reference section at the end)

Yesterday another example was sent to me - which is now "done and dusted" but was drawn to my attention and I thought was worth highlighting to you all. However I thought it might be more useful to put some context around it.

This post is about

• WHAT IS "ripping off" or "passing off" in the context of art - examining definitions of:
• forgery
• imitation
• passing off
• WHAT HAPPENED in the latest example
• TOP TIPS for what to do should artwork being copied happen to you or your friends.

[NOTE: This post has been amended since first published]

Who are artists who "rip-off" or "pass off"?