I feel compelled to point out that the "second party" is the customer, so although it's obvious on reading your post that you don't mean that at all, the subject implies fan-created content.
Fair enough. I honestly had no idea what "2nd party" might ACTUALLY mean, but I knew what 1st and 3rd party were and so I just tried to split the difference.
I might have a doctorate, but that doesn't mean I'm smart!