I have a website that ranks #1-2 for the best social media marketing keywords in its field. I just was browsing around today and came across someone on page 3 with a domain that is almost the exact same (mine is plural his is singular) and he literally has copied all of the content word for word from my website, and tried to make it look as close to mine as he could. I emailed him asking him to use his own content and he has refused to. I guess the best thing to do would be change mine a bit, but than he might continue to do this copying me each time. I'm not really a big SEO guy, but doesn't a site get hurt when it has duplicate content? Any suggestions/info would be appreciated..Thanks!