Portal owners have application segments which is the final step in the registration process. When you view the Application Segment, you will be asked to provide information. If you chose not to provide, the information, you can CLICK TO COMPLETE which is the green action icon. If you can not proceed, that segment is required by the portal owner and must be filled in completely to move on and complete registration.
The portal owners make the determination regarding what is required information and what is optional. This information is used internally on their end for their team to make informed decisions regarding business with your company. It is recommended to fill in all information so that your company profile is complete.