(IANAL)

1 - Posterous, if you're on their subdomain

2 - The business, e.g., Posterous, Inc.

3 - An employee who takes on this responsibility. Posterous' is Sachin Agarwal, their CEO.

Here's Posterous' completed form:

http://www.copyright.gov/onlinesp/agents/p/poste.pdf

1 - What if you're not on their subdomain? I have a Posterous blog and a blog on GitHub Pages, both of which have comments. Am I liable if I don't send the government a $105 check?

If so, I might take a page out of Kyle Neath's book and make people email me if they want to comment: http://warpspire.com/ask/

I don't think it matters legally, but practically, they'll probably go after whoever owns the domain (or whoever looks like the biggest target).

What's legal doesn't really matter though, as $105 is far cheaper than any lawsuit - even one you'd definitely win. So if you're at all worried, I'd cover your bases.

Thanks!

IANAL, but as I understand the law, the 'service provider' who registers is the one who is protected.

Posterous is providing you and anyone who comments on your blog a service - they can register to protect themselves.

You are providing a service by providing stories and allowing people to comment.

Theoretically, without any safe harbour, either you or Posterous could be found to be contributorily liable for copyright infringement in a comment on your blog, since you both provided services which allowed the infringement to occur.

So to answer your questions: 1 - Posterous has registered an agent, to protect themselves, and you might want to register to protect yourself. 2 - You both are potentially Service Providers. 3 - You can designate an agent (which could be you), and Posterous' designated agent on the form they have put in is Sachin Agarwal.

If you are worried, I'd suggest talking to a lawyer with expertise in Copyright law.

Or, for much less than the cost of spending an hour talking to the lawyer, just register and be done with it.