Yes I guess there are some legitimate scrapers, I have seen a couple that use scraped content, but in a useful way and provide a backlink.

So I am always going to run the risk of blocking legitimate visitors and bots if I try to tackle it that way.

The specific problem with the sites that use my sitemap url in a script that shows Googlebot my content as theirs, I suppose is somewhat different to scraping, as they are not actually scraping my site, just trying to trick Googlebot to think that my content is on their website, when it isnt at all.

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