There is an interesting conversation going on at Hacker News on the topic of Google sending webmasters manual actions over links, which leads to those webmaster requesting and sometimes threatening webmasters to remove links from your quality site that you may have never added in the first place.
Heck, I get the requests here fairly often and honestly, I stopped responding.
Anyway, a lot of the topics we've covered here a bunch of times including:
- Google: Being Disavowed Won't Hurt Your Site
- Do You Fear Google Disavow Link Threats?
- Hold Your SEO Client Hostage With Negative SEO Threats
- Time To Get Creative With Your Link Removal Requests
But there are some interesting notes in here from Google's Matt Cutts and Google's Ryan Moulton, outside of all the other interesting discussion around this topic. You should 100% read through the Hacker News thread yourself.
It's not a huge surprise that some sites which went way too far spamming for links will sometimes go overboard when it's necessary to clean the spammy links up. The main thing I'd recommend for a site owner who gets a fairly large number of link removal requests is to ask "Do these requests indicate a larger issue with my site?" For example, if you run a forum and it's trivially easy for blackhat SEOs to register for your forum and drop a link on the user profile page, then that's a loophole that you probably want to close. But if the links actually look organic to you or you're confident that your site is high-quality or doesn't have those sorts of loopholes, you can safely ignore these requests unless you're feeling helpful.
So maybe if you get a lot of these requests, maybe, something is wrong with your site?
Matt Cutts responds next to the claims of negative SEO:
Yes, we work to avoid this sort of attack when designing our ranking algorithms.
Ryan Moulton added the reason why so many link removal requests go out, is not just Google's fault, but the bad SEO is fired and the new one isn't sure which links are bad and good:
The most likely situation is that the company who sent the letter hired a shady SEO. That SEO did spammy things that got them penalized. They brought in a new SEO to clean up the mess, and that SEO is trying to undo all the damage the previous one caused. They are trying to remove every link they can find since they didn't do the spamming in the first place and don't know which are causing the problem.
Of course, Matt mentions he also talked about this quickly on This Week in Google at 4 minutes and 15 seconds in, watch it:
Forum discussion at Hacker News.