I have no idea how this is going to playout but if there's a copyright argument to be made, it won't be on the copyright of each listing, but the copyright on the compilation of the listings.
You can't say the listing belongs to the user on one hand, and then say the data belongs to craigslist on the other.
You can in fact make this argument in the case of compilations in copyright law - think a compilation of short stories or one of those "Songs of the 90s albums" - the initial authors still own their work, but the entity which creates the compilation still owns the right to the entire compiled work.
(I intentionally edited your statement - don't want to bring liability into this, I think its a separate issue and a bit of a red herring w/r/t this discussion).
I don't think it's as clearcut as saying its a compilation.
Here is the relevant wikipedia section on compilation copyright
>Copyright Act allows for the protection of "compilations," provided there is a "creative" or "original" act involved in such a compilation, such as in the selection (deciding which things to include or exclude), and arrangement (how they are shown and in what order). The protection is limited only to the selection and arrangement, not to the facts themselves, which may be freely copied.
>The Supreme Court decision in Feist v. Rural..rejected what was known as the "sweat of the brow" doctrine, in ruling that no matter how much work was necessary to create a compilation, a non-selective collection of facts ordered in a non-creative way is not subject to copyright protection.
I think there is a good argument that there is no creativity on Craigslist's part in selecting postings, since they aren't selecting them--users are uploading them. If true selection wouldn't be covered.
The arrangement might be (if it can be said to be creative), but I'm assuming padmapper isn't copying their arrangement.
You can't say the listing belongs to the user on one hand, and then say the data belongs to craigslist on the other.
You can in fact make this argument in the case of compilations in copyright law - think a compilation of short stories or one of those "Songs of the 90s albums" - the initial authors still own their work, but the entity which creates the compilation still owns the right to the entire compiled work.
(I intentionally edited your statement - don't want to bring liability into this, I think its a separate issue and a bit of a red herring w/r/t this discussion).