Comcast or AT&T or Verizon typically keep their logs for 18 to 36 months.
What we saw was a shift towards customers being made part of a business model that involved -- I don't know if extortion is the right word -- but embarassment for gain. [...] But they would pay the settlement anyway. Because no one wants to be named in the public record in a case from So-And-So Productions vs. 1,600 names including Bob Smith for downloading a film called "Don't Tell My Wife I B---F----- The Babysitter." [...]
We saw a big uptake in this problem early last year. The "Don't Tell My Wife" one was the first, and we laughed about it. But then we saw more and more coming in. So I looked at this, and it was a cynical, awful business.
I met with my system team, and I said, why are we keeping these logs? The primary reasons were law enforcement and spam, so we looked at our law enforcement subpoenas, and the spam processing. In the case of spam, someone is infected and becomes part of a botnet, somebody kicks off a spam job and the customer dumps 20,000 emails in a day. We get complaints, and they're all about the last day. My systems team also only needed logs for a day.
So then I looked at law enforcement subpoenas and tried to balance an ability to help law enforcement when it's morally right to do so with an inability to help anybody beyond a certain window. In the civil copyright cases, we'd get a subpoena from them anywhere from 30-90 days later, sometimes longer after the alleged act of piracy has occurred.
We were concerned about cases where there's a kidnapping, a threat to the human life, and the FBI is trying to find the kidnapper who sent a demand email yesterday or a week ago. We felt like two weeks was a good window that would allow us to address some things -- both our own needs in the long term and the law enforcement's dire needs in the mid-term -- while omitting any ability to assist in what we felt was like an extortion racket.
Sonic.net has been my ISP for years, and I've been very happy with them. Besides things like the above, they've been incredibly reliable and their support staff know what they're talking about.
The only downside is that installation can take a while, because they use AT&T copper. Since AT&T has no incentive to help a competitor, that tends to add 2+ weeks to any installation.
If you're in the Bay Area and using AT&T or Comcast, I'm pretty sure you have no rational reason to continue to do so.