Clear-cut acknowledgement of the impact of negative SEO

Selected answers from the Dumb SEO Questions Facebook & G+ community.

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  Dan Thies: Jim, I don`t think there have been many times during Google`s existence that I wasn`t aware of at least one way that a third party could knock a page off of a SERP, out of the index, or hijack some or all of the canonical URLs for that page. Some of these issues became public, and I helped patch them to the degree that Google was willing to be helped. My rather noisy public disclosure about proxy hacking to de-index pages won us all an official search-engine-approved method for verifying the identity of their bots. This here? He`s very carefully saying nothing, but the job they have to do is harder than you think. Any sufficiently complex system WILL develop emergent properties that are not part of the design.
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  Steve Gerencser: 100% agree Jim. I`ve been preaching that about Google for many years. It`s a side effect of the type of people that work there.
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  Jim Munro: I hear what you are saying, Dan, but Google is unique in that other search engines like Bing have always simply ignored negative signals. Google consciously stayed the course and even accepted a measure of what they quaintly call "Collateral damage" - the percentage of innocent sites estimated to negatively affected by an update. Even if they find a moral compass and fix their problems now, I think Google should still be held to account for dealing with people`s livelihoods in such a cavalier fashion.
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  Jenny Halasz: I`ve seen sites where neg SEO has been attempted, but there`s three major problems... 1. It`s impossible to isolate signals and say definitively that those bad links spoiled the bunch, and 2. It`s impossible to prove that the links weren`t created by the site owner, and 3. It`s impossible to know definitively (unless you`re Google) if those links were used or ignored. That`s why we have no proof that #NSEO exists.
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  Jim Munro: I have the proof of my own experience, Jenny Halasz, Roger Montti, combined with the knowledge that we did not create the links for the targeted sites. I also know that Google introduced upper-limit thresholds unique for each site. Hit that threshold and die. No other search engine did this. I also know that Google chose to accept a percentage of (their term) "collateral damage" ie a percentage of innocent sites negatively affected by an update relating to these thresholds. No other search engine did this.
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  Roger Montti: How is " I don`t see any negative-SEO effects" a clear cut admission that negative SEO exists? What am I missing?
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  Jenny Halasz: Not arguing at all! Just pointing out it`s difficult to prove with statistical data.
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  Jim Munro: Roger Montti - it would be better to use the whole quote viz "Double-checking some of that, I don`t see any negative-SEO effects in play. From our point of view, your site is ranking normally." To be able to make that statement, a definition of "negative-SEO effects" is required. You cannot rule something out if you do not know what it is.
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  Ammon Johns: Put it this very simple way - if you as an SEO have ever, EVER, fixed anything that you knew could harm or tank a sites ranking, then obviously the reverse could be done. Most of the successful forms of negative SEO are effectively nothing more than spotting a flaw in the design or function of a site that is currently not a problem, and then finding a way to make that flaw a problem. Have they forgotten to make their search pages non-indexable? Then create a few thousand PBN pages and links each with 50 or so links to pre-populated, zero-result searches on that site, etc.