I don't know, surely if the site has links to copyrighted material they can request it be removed, like how google has to remove links to copyrighted material?
I could only talk of my nil to limited experience in answer to that question, however it doesn't relate to pebble at all nor am I sure it has much of a comparison.
I am sure you know of Torrents, but alot of people have never heard of NZB's (Usenet) ... Long story short, movie companies have finally started to worry about Usenet and as such they issue Take Down Requests to the servers that host the files. However all of the links on all of the thousands of sites that link to those NZB's are still there, and nor do the individual sites get a Take Down Notice for the links (that I am aware of), only the place that hosts the actual files gets those requests.
Now it could be argued that it is easier to send 1000 take down notices (ie to the server farms) instead of sending 100,000 take down notices (ie the sites that host the links) for each link, as removing the files would be much easier and achieves the job, but all of the links to those files are always available (well for up to 3 years as far as I am aware).