Here are few items to know when you create a profile into the Developer Community.
To create a profile into the platform is completely free.
Username needs to be unique and it is used to login to the platform in the future.
Company invite code is used to send a request to join a specific Company that already exists in Syniverse Developer Community. The Admin user of the Company needs to accept the request to join before the user requesting to join can see the Company environment. By default any user who joins a Company only has limited entitlements until the admin user adds additional entitlements.