Bing queries with special characters yield 403

Hello,

We have been seeing an odd occurrence with a site where certain queries within Bing will yield a 403 error when using the link within this search to go to a site. Today I have been able to watch live access logs, and determined in this case an apostrophe in the search query is the difference between the 403 and intended site load.

Here is the log entry for the failure (note the %27 within the query passed from Bing):

162.158.127.184 - - [29/Aug/2016:13:36:39 -0400] "GET / HTTP/1.1" 500 - "http://www.bing.com/search?q=what%27s+the+best+pr+firm+in+san+francisco%3F&go=Submit&qs=n&form=QBLH&pq=what%27s+the+best+pr+firm+in+san+francisco%3F&sc=1-41&sp=-1&sk=&cvid=E20D357824014005A2F3D89D32F80622" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.112 Safari/537.36"

Here is the entry where the apostrophe was omitted from the search and the site load was successful:

162.158.127.184 - - [29/Aug/2016:13:48:17 -0400] "GET / HTTP/1.1" 200 14277 "http://www.bing.com/search?q=whats+the+best+pr+firm+in+san+francisco%3F&go=Search&qs=n&form=QBRE&pq=whats+the+best+pr+firm+in+san+francisco%3F&sc=0-40&sp=-1&sk=&cvid=7C9B3119D47B4C95B16FAA04CEE35248" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.112 Safari/537.36"

What would be the best way to resolve this issue, and other potential characters that would also cause this to occur?

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