I heard a while back that Google is able to manipulate form results so that the Google bot can index the information after a form has been completed.
I have just seen an instance of this has actually happening on Brand Republic and i wouldn’t think Brand Republic will be too happy about it!
I searched in Google for ‘ad agencies tables‘ the first result is from Brand Republic. Having clicked on this you can clearly see the agency table: 
However, if you go directly through the URL then the user needs to enter their log in details:
I have tried to crawl the site as a Google bot and see if this is something that Brand Republic want to happen but the login details are still displayed to the Google bot, meaning Brand Republic are losing out on loads of user data through Google automatically bypassing their forms.
To resolve this i would suggest that Brand Republic and anyone else with the same issue uses their robots.txt files to exclude the search engines from crawling past the form pages. If you are unsure of how to do this please leave me a comment below and i’ll detail it for you or have a look at this post by Google.
