Unfortunately currently we do not have this such of feature to protect copy content, if you mean those visitor come into your site and use the highlight and copy action, you can apply following css into your current template css :

#ed {

  -webkit-user-select: none; 

  -moz-user-select: none; 

  -ms-user-select: none;   

  user-select: none;           

}

So they unable to highlight the content on the page.