I don't of anything current that can make use of it. My guess is that it's for future use, or use by third party applications such as Crystal or Excel, etc.
 
There is a Class that can be used as a filter in printing, and an RTM Print Group that can be used to print different forms but I'm guessing you're already discovered those and have other purposes for them.

That is strictly a reference field, it does not control anything.  If you want to add it to a report or include it in a query, the actual field is BKAR_REQD_CERTS and it is 10 characters.