When using StartPage I get asked to complete a capcha. Why is Startpage asking for a Capcha? Is StartPage identifying or spying on me? Is StartPage compromised or is it safe?
This is not a indication that Tor is compromised
The captcha on startpage.com is used to prevent data scraping by limiting the number of searches. When the limit is reached a captcha is shown.
Tor exit nodes often reach these kinds of limits since a lot of traffic goes through only a few exit nodes. From StartPage view it looks like one user does a huge amount of searches.
From StartPage support:
StartPage and Ixquick use CAPTCHAs to confirm that you are a user of our service.
Sending a large number of StartPage searches in a short period of time can result in StartPage asking you to complete a CAPTCHA. Once you complete a CAPTCHA, you won't need to complete another one unless you exceed the request limit again.