Vanguard CEO McNabb to Step Down

Buckley joined Vanguard in 1991 as an assistant to then Chairman John C. Bogle. He was elected as a principal of the firm in 1998 and served as chief information officer and head of Vanguard's Information Technology Division from 2001 to 2006 and head of Vanguard's Retail Investor Group from 2006 to 2012.

"This information and technology management experience will serve him well," since Vanguard relies on technology "and huge scale" to keep its costs low, McDevitt says. "That experience will be important for them going forward."

As for Buckley's personality, "He is more like McNabb than Bogle," the analyst said. "There is never going to be another Bogle, who is an original. He was right for the firm [when he led it] and continues to be an investor advocate."

Overall, given that Buckley worked as Bogle's assistant and that he has been at Vanguard for his entire career, "There should be tremendous continuity in the firm's culture," according to McDevitt.

As of June 30, Vanguard managed $4.4 trillion in global assets. It sells 369 funds to more than 20 million investors worldwide.

"Vanguard's mutual structure and client-focused culture serve as the foundation for everything we do, and I am honored to lead this great organization into its next chapter," said Buckley in a statement.

"Thanks to Bill's strong leadership over the past 10 years, Vanguard is well-positioned to continue helping clients achieve investment success. I look forward to continuing to work closely with Bill over the next six months as I transition to my new role," he added.

McNabb joined Vanguard in 1986 and became head of Vanguard's Institutional Investor Group in 1995. He was named CEO in 2008 and chairman in 2009.