I'm not sure his distinction between those who have enough wealth to engage in wealth defense and those who do not stands up. There are plenty of people who he does not seem to be counting as oligarchs who hire financial professionals to ensure they pay the minimum amount of taxes possible. The difference between the 5%ers with their stock brokers and accountants and the ultra-rich .1% with their high-powered teams of tax evasion experts seems to be one of degree, not the qualitative difference he seems to believe it is. Some quantitative line between the merely rich and the oligarchs is probably still necessary.

His argument that oligarchy and democracy are compatible seems to only be true for certain narrow conceptions of democracy (liberal, Schumpeterian, etc).

His distinction between tamed and untamed oligarchies is rather unclear.

However, this is an important topic, and this is one of the few texts that attempts to theorize oligarchy as a distinct phenomena. I also appreciated that his theory was linked to case studies, a move not often seen in theoretically inclined texts. Overall, a good read. ( )