Do I Need a DBA   if I have filed a Corporation

(If you do business in a name other than the corporation's name, you need a DBA.

 For example if you are a corporation doing  business as the corporate Document name (xyz, inc),  you don't need a business. 

However, if you xyz, inc doing business as "Rob 'em & Cheat 'em"  You need a DBA under the corporate name.