A little while ago I had an NYC agency (they should know better) lift shots from my website and use them as a front page to a case study for one of their clients (can you believe this?).
So I contacted them and they took them down and said that was it. I said "no it wasn't". Breach of copyright and reputation damage (I was contacted by the client for whom I had originally shot the images, a big, litigious company, mad with me because they thought I was selling pictures of their staff. I calmed them back down to happy). Then I got an email, or a cut and paste from their lawyer saying they had taken them down and they would not enter into any further discussions.
To be honest, all I wanted was an apology. I'd not have got much of a fee out of them, and could not be bothered to chase them through the courts with lawyers. Too much faffing and I am UK based, they are US. Complicated.
So I wrote to the director of corporate communications at the agency's client, saying the agency had breached copyright on their case study and would not speak to me, so all I can do is ask him if they had ever offered him any stock images for their work. That did the trick...
Two days later I had the president of the agency on the phone apologising like mad and telling me he was unaware of what had happened but was now busy kicking backsides. Good enough for me.
I say this because sometimes it's better, easier and potentially less costly to try and leverage a response rather than digging your heels in and getting embroiled in an increasingly vindictive spat. When you get into a position where you don't feel you can back down, things can get uglier than they need to.