I would like to start a thread about the effect that different types of scraped or duplicate content can have on a website. I have sometimes heard that if your content is duplicated on another website, it won't really affect your rankings and I have also heard that if your content is duplicated on another website, it can have an effect on your rankings.
Below are a few ways that I have seen a website's content scraped and duplicated, and I would really appreciate your thoughts regarding the impact that it can have on your website. I should also mention that when I say content has been duplicated or scraped, I mean a large part of the body text or the entire body text of a page on a website is appearing on another website(s).
(1) If your content is appearing on other site(s) and there is no link back, can it impact your rankings? If it can, is it rankings for certain keywords that the content ranks for that is affected or is there an overall effect on your site?
(2) If the content is appearing on other sites but there is a link back to your site, will there be an impact on your rankings? If there is an impact, would it be specific or more overall in nature?
(3) If the content of a page on your site was copied by another site with a link back to your site and the other site also tags the content with many keyword phrases so the content is essentially appearing on many pages of the other site with a link back to your site, would your site be affected? (I know that this question is kind of long, but it is a situation that I am facing)
(4) If your site's content is appearing on other websites, but when you do a search for a unique string of text in quotes on a search engine and your site appears first in the SERP, does it mean that although the content of your site has been duplicated, it is not impacting you?