I recently added 4 of our websites in Bing Webmaster Tool. I had to verify the ownership for all the 4 websites. Like GWT, I was given with an XML file for each Websites that I need to place in the root directory of my domain.
My concern is that the XML files available in the Bing webmaster tool for verification are the same for all the 4 Websites. Is that common?
A SINGLE VERIFICATION code for an account? No matter how many websites are added in that account?
It appears to be, all my Bing authorization files are identical. Why would they need to be unique? I can't add your sites to my Bing Webmaster account because I can't upload the Auth file to your hosting.
Just for the record my Google WMT auth files are identical too.
To me it would be more surprising if they were different. After all, the whole point is that you're the same person with the same account. Consider the alternative: four sites, four codes. Oops, sorry, you uploaded the code for Site A to Site B, and accidentally put the same code on both Sites C and D, and...
The more crucial question is: Are the different accounts' codes different from each other? Otherwise anyone in the site-design business could wrap it up by dropping a copy of the validation code in everything they design, and claiming for ever afterward that it's their site. Especially handy if you later design one for the competition. "OK, let's see which keywords worked best."