It's clear that Companies are made at account level. But for certain projects we need only a part of all companies to be activated.
So, an option to activate or deactivate a company to a project is needed. When setting up the project the Account admin can validate the company that should be activated for the certain project. By default all companies can be activated, so only the companies this project doesn't need can be deactivated.
For example, we have a confidential project with confidential companies in it, now the project admin and other users will see all companies, also the companies for projects they are not allowed to see. Also in the transmittal tool, all users can see all roles and companies.