A pyramid scheme is one in which the only way the business stays afloat is by attracting new buy-ins (as opposed to selling product). Tesla keeps issuing new stock every so often, and somehow, every time they do the price goes up. Their most recent issue was to the tune of $800,000,000, for example. Not exactly chump change. Fortunately for them they have a lot of Wall Street stock manipulators (oops, I mean boosters) willing to pump their tires for them. Remember the housing bubble? The same thing is going to happen to their stock as soon as the slightest thing goes wrong. My assumption is that the thing will be when they pre-sell a bunch of $35k cars (also sign of trouble that they feel the need to collect revenue before they can even manufacture the things), and then can't deliver them on time at that price. I base this on the fact that they can't make money selling cars at $100k.