I have one question. One mate have website where he upload articles which came out on 10 other sites. So it means that on this website is non unique content.
Now he wants move up this website on better positions in search engines. He will from this moment public only unique content.
Main question is: To which extent will old non unique content to harm this website? Will the previous non unique content worsen the default site position in the eyes of the search engines?
Thanks in advance.