The letter was not friendly. It said, "Pay us $5,000 and we won't sue you."
The letter was from a law firm in Los Angeles and the attorney represented an artist who artwork we used in a blog. The letter explained that we had used the artwork with out the permission of the artist.
We got the artwork from an online site that stated everything on the site was free and could be used.
I visited my attorneys office with our IT person who was really enraged over the request for the money and wanted to "do battle til death" (OK he's French) The attorney we were assigned to is a specialist in Copy-write Law and she simply told us to pay the money. She explained that even thought we took the art from a 'free' site that how did we know that the artist gave permission to the site to post his artwork.
I guess if the suit were for $30,000 or $40,000 that we would try to fight and would investigate whether we were wrong or being wronged. But at $5,000 our attorney encouraged us to pay the ransom. We did and I no longer use artwork from the Internet - even if it says "free" or even if they will pay me !