The Tesla Demo That Happened on SpaceX's Property

Elon Musk showcased a vehicle at a facility owned by SpaceX, and SpaceX helped develop the model, the BBC reports. That arrangement is its own story: a Tesla product, engineered in part by another of Musk's companies, presented on that company's ground.

Optimist: Help is help. Getting the other company in the family to develop part of the model is a genuine head start, regardless of which logo ends up on the badge.

Skeptic: The blurrier the line between the two companies, the harder it is to tell what exactly you own when you buy shares in one of them.