Do content thieves keep you up at night, tossing and turning in your bed, worrying that someone evil person might steal you content and you may never know about it. This is a problem for some people, and especially those that write articles and post them freely on their sites. Sometimes a copyright notice just doesn't cut it. There is a good thread over at Highrankings, asking about how to protect your copy, but still allow spiders to get access to it. The member who started the thread said they had considered cloaking as an option, but quickly decided other measures were better suited for this. There are some gems of advice in there that I will highlight below.
Ways to Protect Your Content & Allow Search Engine Spiders
1. Monitor Your Competitors. Send out notices should you see they are the midnight bandits that ran off with your content with permission.
2. Use a Copyright Notice. At the end of all your pages.
3. Try Putting a Transparent Layer Over the Area. This will prevent the text from being copy and pasted outside the site.
4. Use CSS or a Liquid CSS Layout to prevent copy and pasting. Due to how CSS arranges content sections, it prevents most people from copy and pasting sections. If they try they usually end up with highlighting the stuff they don't want, or the entire page.
5. Use a Disable Right Mouse Click Script. or similar script. This is one I have used in the past and continue to like mainly just for images on my blog. Basically it prevents people from viewing your source, lifting your images off the sites, or stealing your webpages. You can find a version of the disable right mouse script here.
6. Lock Down Your PDF documents. Not sure exactly how this is done, but it was mentioned as one way to prevent downloading or copying.
7. Your Own Research. Stopping those that steal your content is best served if your do it yourself.
Its seems to be rather difficult line between protecting your copy and still providing spiders with all the stuff they need. As one member, chrishirst, pointed out, who is to stop competitors from looking at the Google cache, even thought you have done all these things to protect it? If anyone has any more suggestions on protecting your content, please post them in the comments section. If I get enough I will update the article with them for a more comprehensive list.