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I'm a website developer, and in the past I have usually added a tiny backlink to the footer of my clients' websites like this: Website Design by MyCompanyName I understand that Google sees this as a low-quality backlink.  However, I was wondering if such links can hurt my rankings.  Does Penguin sees these links as spam?  If so, should I add a rel="nofollow" to the links?  Is there anything else I should change? I do not want to remove these links completely because they are good for marketing my business.  I just want to minimize any negative SEO impact of the links. I appreciate your input.  Thanks.