California voters rejected Proposition 40, a one-time 5% tax on billionaires.
Tech leaders led the opposition and outspent backers roughly 10 to 1. That is all the spending figure establishes: opponents had far more money in the fight, and the measure failed. It does not say how many voters were moved by the campaign and how many by the idea itself.
Before the vote, the founders and economists TechCrunch interviewed were split on what the tax would have done. Some argued it would drive wealthy residents out of the state. Others argued it would simply trim their fortunes. The vote settles neither point, because a measure that never takes effect produces no evidence about how billionaires behave once it does.
That leaves the central dispute exactly where it started. The design also shaped the argument. A single levy is a narrower test than an annual wealth tax, since a one-time charge is a weaker reason to uproot a household than a bill that returns every year. Supporters of a future version could point to that gap. Opponents can point to this result.
The open question for backers is whether a 10-to-1 spending deficit is something a revised proposal can overcome, or whether the structure of the fight matters more than the structure of the tax.