The company name and physical address on your account are the details that are displayed in your email footer. This is for CAN SPAM and other law compliance purposes. But you can edit and add to these details, easily!
How to Change Company and Address Information:
Click on Settings at the top of your account page.
Edit the Company/Group details in the field. You can add extra information into this field, as well -- it doesn't have to be just your company name.
Edit the Physical address details in that field. Again, you can add extra info in here, if you want. Like maybe telephone number!
Make to sure save any changes by clicking on Save account info.