News Courtesy of SearchEngineLand.com:
Have you ever experienced a rankings decline and suspected it was due to something a competitor was doing?
For this second article, we are going to focus on the process of diagnosing whether or not you’ve been hit by negative search engine optimization (SEO) techniques.
If you need a refresher or missed the first article, here it is: What Negative SEO is and is Not.
As you progress through the following steps to try and diagnose what happened, you’ll need to honestly ask yourself whether the decline you’re facing is more a result of your own actions or due to someone acting against you.
It’s an important distinction; your first inclination can be to assume someone is out to hurt you, while it might actually be something as simple as accidentally no-indexing your index, disallowing critical paths in robots.txt or having a broken WordPress plug-in that suddenly duplicates all your pages with strange query parameters and improper canonicalization.
Ryan’s Take 
I’ve always worried about a competitor trying to run a negative SEO attack against me or my clients. It takes a certain kind of low to sabotage the rankings of another website. It’s one thing to try and employ a black hat technique to boost your own rankings. Quite another to destroy the rankings and organic traffic of someone else.
Fortunately, to my knowledge, I’ve never experienced such a thing. No matter how hard I’d like to be #1, #2, or #3; there is no way I would maliciously attack a competitor like that. If anything, it would make me work harder to boost my website in Google. Also, I do believe that Google has taken steps to reduce penalties for certain signals. Instead, they seem to be favoring devaluing links, content and other offending material. This would severely negate potential attacks and render them mostly ineffective.
Moral values aside, It probably isn’t the smartest thing to attempt a smear campaign against a competitor. Think about it. Google is a multi-billion dollar company. They have all this data with which to filter and sort. It wouldn’t be too far-fetched to assume that they could pick up on patterns or signals and apply a penalty to an attacker. If an unnatural link profile suddenly appears overnight they might start to look at similar sites and look for any sort of correlation. If it is discovered there is a commonality between a site plummeting and another on the rise, it may lead to a penalty on the attackers’ website.
Of course, all of this is speculation. To spend efforts on negative SEO when you could use that time to work on SEO for your own site is foolish. As I’ve come to learn, rankings with Google require patience. Keywords will ping pong in positions until one day you’ll see the big jump or Google Dance. You just have to commit to a long campaign of SEO, wait, and wait until the results pay off.
