They're operating a business where ALL operating expenses are paid for by what are, in effect, donations. They don't need to use their own money. They don't need to use consolidated revenue from past game sales (there are none). They don't need business loans. They don't need investors to inject more funds to buy their remaining shares. The owners (other than Calders) have absolutely no financial risk whatsoever.
They have a seemingly unlimited river of funds with little or no conditions, other than an obligation to deliver a game, and even that obligation is dubious.
The owners have shored up their own equity in a maze of companies built from these donations, and their share prices have been growing and solidified by the minority investors who, by investing, have established the benchmark share price, potentially valuing Chris Roberts' shares in the hundreds of millions of dollars.
I keep telling you good people, this is one of the best business models you could ever hope to imagine, even in your wildest dreams.