You can't do that with public financial statements. When preparing financial statements, there is a process called intracompany balancing, where you pull out any revenue/expenses that were generated within the reporting entity.
If that nonsense was allowed, then every company would show revenues in the billions. The finance department would pay the the HR department for HR services, the marketing department would buy millions with their own company, etc.
It is common for internal accounting books to record these intracompany expenses/revenues for record keeping. For instance a TV Show pays for ads on the same network, but before Disney reports profits publicly all of that accounting cruft must be removed.
Not allowed. Any related parties have to be disclosed and will be removed on consolidation of financial statements. Unless both parties are totally separate entities with no relation, we are moving into fraud territory.
