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Just recently we noticed that google has indexed truncated urls for many of our pages that get 301'd to the correct page. For example, we have:
http://www.eventective.com/USA/Massachusetts/Bedford/107/Doubletree-Hotel-Boston-Bedford-Glen.html as the url linked everywhere and that's the only version of that page that we use. Google somehow figured out that it would still go to the right place via 301 if they removed the html filename from the end, so they indexed just: http://www.eventective.com/USA/Massachusetts/Bedford/107/ The 301 is not new. It used to 404, but (probably 5 years ago) we saw a few links come in with the html file missing on similar urls so we decided to 301 them instead thinking it would be helpful.  We've preferred the longer version because it has the name in it and users that pay attention to the url can feel more confident they are going to the right place. We've always used the full (longer) url and google used to index them all that way, but just recently we noticed about 1/2 of our urls have been converted to the shorter version in the SERPs.  These shortened urls take the user to the right page via 301, so it isn't a case of the user landing in the wrong place, but over 100,000 301s may not be so good. You can look at: site:www.eventective.com/usa/massachusetts/bedford/ and you'll noticed all of the urls to businesses at the top of the listings go to the truncated version, but toward the bottom they have the full url. Can you explain to me why google would index a page that is 301'd to the right page and has been for years? I have a lot of thoughts on why they would do this and even more ideas on how we could build our urls better, but I'd really like to hear from some people that aren't quite as close to it as I am. One small detail that shouldn't affect this, but I'll mention it anyway, is that we have a mobile site with the same url pattern. http://m.eventective.com/USA/Massachusetts/Bedford/107/Doubletree-Hotel-Boston-Bedford-Glen.html We did not have the proper 301 in place on the m. site until the end of last week.  I'm pretty sure it will be asked, so I'll also mention we have the rel=alternate/canonical set up between the www and m sites. I'm also interested in any thoughts on how this may affect rankings since we seem to have been hit by something toward the end of last week.  Don't hesitate to mention anything else you see that may have triggered whatever may have hit us. Thank you,
Michael