To include highly relevant content in Google's search index. This provides a better experience for Google users who may not have known that content existed.
To provide a promotion and discovery opportunity for publishers with restricted content.First Click Free is designed to protect your content while allowing you to include it Google's search index. To implement First Click Free, you must allow all users who find your page through Google search to see the full text of the document that the user found in Google's search results and that Google's crawler found on the web without requiring them to register or subscribe to see that content. The user's first click to your content is free and does not require logging in. You may, however, block the user with a login or payment or registration request when he tries to click away from that page to another section of your content site.
Webmasters wishing to implement First Click Free should follow these guidelines:
All users who click a Google search result to arrive at your site should be allowed to see the full text of the content they're trying to access.
The page displayed to all users who visit from Google must be identical to the content that is shown to Googlebot.
To include your restricted content in Google's search index, our crawler needs to be able to access that content on your site. Keep in mind that Googlebot cannot access pages behind registration or login forms. You need to configure your website to serve the full text of each document when the request is identified as coming from Googlebot via the user-agent and IP-address. It's equally important that your robots.txt file allows access of these URLs by Googlebot.
When users click a Google search result to access your content, your web server will need to check the "Referer" HTTP request-header field. When the referring URL is on a Google domain, like www.google.com or www.google.de, your site will need to display the full text version of the page instead of the protected version of the page that is otherwise shown. Most web servers have instructions for implementing this type of behavior.
Frequently Asked Questions
Q: Can I allow Googlebot to access some restricted content pages but not others?
Q: Can I limit the number of restricted content pages that an individual user can access on my site via First Click Free?
A: No. Any user arriving at your site from a Google search results page should be shown the full text of the requested page.
Q: Can First Click Free URLs be submitted using Sitemap files?
A: Yes. Simply create and submit your Sitemap file as usual.
Q: Is First Click Free content guaranteed inclusion in the Google Index?
A: No. Google does not guarantee inclusion in the web index.
Do you have any more questions or comments? Come on over to the Google Webmaster Help forum and join the discussion!
Link - from Google Webmaster Central Blog
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