How to Tell Google Not to Index a Page in Search Results [Quick Tip]
Hubspot
MARCH 30, 2013
So if your thank-you pages are easily discoverable through a simple Google search, you may be leaving valuable leads on the table. Visitors will have easy access to your lead generating offers without having to provide you with their information to pass through your "gate" -- in other words, the lead-capture form on your landing page.
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