Penalty on off-niche off topic backlinks

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

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  Roy Cohen: People will go to great lengths to do things the wrong way. Some stuff still works and I see competitors ranking with shit links/content all the time. Does that mean you should do it too? No, play the long game. Eventually, all these sites go to 0.
  
  
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  Roger Montti: Are you constantly monitoring your competitors backlinks at all times?Or did you notice the back links after changing rankings?
  
  Those links would not affect your competitors rankings. If they had any effect they would make it rank for the adult keywords but not for anything relevant to the site.
  
  Additionally that is comment spam so that has no effect either, it`s super easy to ignore.
  
  What you`re seeing is pure coincidence. And I have a feeling that you never noticed those links until you went checking after your clients site started going down.
  
  So it might be that those links had already been there.
  
  One thing I`m confident of is that those links had zero to do with the change in rankings.
  
  
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  Trenton Erker: Roger Montti Second this.
  
  
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  Michael Zittel: Keep watching. I bet your competitor tanks shortly.
  
  
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  Jeff Ferguson: Wait it out… while it probably caused a shift in the short term, it won’t last with crappy tactics like that.