Comment by the_mitsuhiko

They are still distinct public companies and they want to merge them. And even today the amount of cross mingling between those two entities however is quite significant. You would not necessarily know that they are independent from each other.

The roadster uses Space X propulsion tech, the cybercab uses starlink, grok is in all Tesla cars, both companies share Terafab. But then Tesla also supplies batteries and cybertrucks to Space X etc.