I know Zuckerberg is rich from creating Facebook, but where did Chan find her stash of money? Or are they donating Mark's money but using both people names? Asking out of curiosity, not trying to make some dumb point.
It's not quite that simple. California, where they live, is a "community property" state[1]. This means that anything earned while married is community property - owned 50/50 by both people. On the other hand anything you had before marriage (or inherited) is "separate property" - owned 100% that person.
Due to these rules the fact they were married after - one day after! - the IPO could make a big difference if they were to ever divorce[2]. Of course, like almost every very wealthy person, they likely have a prenuptial agreement which should establish exactly who owns what.
The indignation of the form of your question is remarkable.
But to answer your question: It's probably funneled through their foundation, which they would, of course, name and manage together. Because, ya know, they're married.
The HN is headline is inaccurate. Zuck wrote "Priscilla and I", because "I and Priscilla" is ungramattical in American language/culture, and "I" is... uncouth.
Changing the headline's speaker from Zuck to "anonymous HN software" changes the meaning.