Ways to find private - non-indexed forums in a niche

[ilyaelbert]

I would wondering if there were ways to find non-indexed content in private forums/discussion boards. Is there a scalable 'foot-print' that suggests the forum has a private section?

[KeriMorgret]

I don't have an answer to this question, but I'd approach it by looking at the major forum software providers and seeing what the default text is that they use for private forums to show to non-users, then search for that text. Some people will change the text, but that may be a starting point for you.