If the firm name is stored as a text box on the invoice format, you may edit each format one at a time to adjust the firm name. See the Knowledge Base article on editing text boxes.

Note that if the invoice styles pull the firm name from the system settings variable in Orion Administration under the Firm Information/Licenses Tab, you will have to contact Orion support to change these fields. 

This Firm Name field in System Settings also controls what prints in the footer section of all your reports. Firms are licensed for one firm name when they initially purchase Orion. If the firm name changes, the firm administrator will need to contact Orion Support to provide the new name and request that the protected Systems Setting for the firm name be edited.