Hardline? Or, wifi?
You'd have to ask your ISP what they mean by that. I suspect it means that they received the subpoena from a law enforcement agency.When my ISP says "law enforcement", does that necessarily mean that a specific law enforcement officer is requesting it?
Law enforcement is not going to be investigating civil matters. To utilize a subpoena, a criminal investigation must exist. However! That does not mean your IP is a suspect in this, it might be meant to identify other victims or potential witnesses of someone else's activity that crossed your path.Or is it that every subpoena must be backed by "law enforcement", but could be initiated by a private party over a civil suit or private investigation? Is there any way I can get my ISP to cough up a copy of the subpoena? Or would that even help?
Unless you want to go to court and see if a court will compel the ISP to provide a copy of the subpoena, about all you can do is ask.

