I found this on the Intuit website:
I have a corporation -- should I file a DBA for my corporation?
Another common reason to register a DBA is when your state-level entity (such as a corporation or limited liability company) has a division or unit that conducts business using a variation of -- or a completely different name than -- the true name. For example, a bank whose true name is "ABC Bank Inc." might market their mortgage services on a website called "abcmortgages.com" and might have a separate division for their loan services called "XYZ Lenders," in which case they would most likely file DBAs for both "abcmortgages.com" and :"XYZ Lenders" in all jurisdictions in which these names are used.