"BlackRock’s size is mind-boggling. With almost $4 trillion under management, it is, according to a recent University of Michigan study, the single largest shareholder in one of every five United States companies. It manages money from pension funds and endowments as well as retail investors, controls large stakes in companies like JPMorgan Chase, Wal-Mart and Chevron and owns 5 percent or more of roughly 40 percent of all publicly traded companies in the country."
This article describes how Blackrock uses their powerful influence during proxy season. Something Vanguard could learn from IMHO, and something that Mr. Bogle has been passionate about.