"Basically, Google's position is that we prefer no hidden links, no hidden text, no automatic tools used for positioning, and no cloaking. We prefer that Googlebot get the exact same page that users see. In general, you can assume that we're as conservative as possible. We don't like hidden links/text in divs/layers/iframes/css, or links that are inconspicuous or punctuation, for example. Similarly, we don't like cloaking or sneaky redirects in any form, whether it be user agent/ip-based, or redirects through javascript, meta refreshes, 302's, or 100% frames." Google also states that "We will not comment on the individual reasons a page was removed and we do not offer an exhaustive list of practices that can cause removal. However, certain actions such as cloaking, writing text that can be seen by search engines but not by users, or setting up pages/links with the sole purpose of fooling search engines may result in permanent removal from our index." More details are available at: Guidelines and
SEO Issues. Also, for copyright violations use the Google DMCA page.