Google's Structured Data Testing Tool? No Data

[YMD]

I'm stumped as to why some of the pages on my website return no data from Google's Structured Data Testing Tool while other pages work fine and return the appropriate data.

My home page http://www.parkseo.net returns no data while many inner pages do.

http://www.parkseo.net      Returns No Data

http://www.parkseo.net/citation-submission.html      Does Return Data.

I have racked my brains out trying to figure out why some pages return data and others don't.  Any help on this issue would be greatly appricated.

Cheers!
Gary Downey

[MattAntonino]

I'm not sure why the citation page returns a preview but to be fair, it's a tool to test your markup and the page that's not returning anything doesn't have any rich snippet markup, does it?

In troubleshooting, it says:

Have you supplied enough information?

Google needs certain data to generate a rich snippet preview for each product type. For example, a Review without a reviewer or a Review-aggregate without a count will not generate a preview. A Person without enough marked-up information, or an event without a date or venue, won't generate a rich snippet either. To see required properties, check the article for each content type.

So maybe it just sees the main page as "not enough info" - although again, why it returns any preview on sub-pages is beyond me.

[YMD]

I added 2 new web pages over the weekend and the information showed up immediately in the tool. The structured data tool does not index, it goes out and pulls in the current live data from the Title Tag but it does not display the description data.  To test this change the data in the Title Tag and refresh the preview button and the data is updated immediately.  From my observation Google only needs Title Tag info to display a Rich Snippet.  Go ahead and test it.  In fact you can add a new page to your website and a Rich Snippet shows up immediately.  This is why I am stumped.

I have resubmitted and indexed the entire site through the webmaster tool.  I'll just have to wait and see if that makes a difference.

Thanks for you input Matt.

[Stevej24]

Our site had been showing up in the structured data tool since it began. All of a sudden within the last few days we noticed that when we type in our home page the message no longer shares our author data, and schema, but returns: Invalid URL or page not found

When we use the html tab and add our code, all our mark ups are showing up.

We are baffled as the site is still indexed on google.  We have applied the same code to two other sites, and they work fine.

[MichaelC-15022]

Steve, if you ever figure out what the problem was, please let me know.  I've got two different client sites that have the "invalid URL" problem.  I've dug through and cleaned them both up via the usual HTML validator, thinking maybe it was some unclosed tag or something sending the parsers off into La-La Land....to no avail