I'm not sure how they can be considered to be doing much, or any, good, when effectively they are passively siphoning off profits and despite all the "good" they do, as a class they get rapidly richer every year. That has always been a conundrum behind Bill Gates' charity. Of course, it's not really a conundrum. The charity is just tax-advantaged PR or tax-advantaged complementary investment masquerading as goodwill.