Rob Arnott is Partner and Chair of the board of Research Affiliates. Rob founded Research Affiliates in 2002 as a research-intensive asset management firm and plays an active role in the firm's research, portfolio management, product innovation, business strategy, and client-facing activities. He is co-portfolio manager on the PIMCO All Asset and All Asset All Authority funds and the PIMCO RAE™ funds. Rob also serves on the firm's Executive Committee.

Prior to establishing Research Affiliates, Rob was chair of First Quadrant, LP, which he built up from the former internal money manager for Crum & Forster into a highly regarded quantitative asset management firm. He was also a global equity strategist at Salomon Brothers (now part of Citigroup), the founding president and CEO of TSA Capital Management (now part of Analytic Investors, LLC), and a vice president at The Boston Company. Over his career, Rob has sought to bridge the gap between academic theory and financial markets, challenging conventional wisdom and developing innovative solutions designed to add value for investors. He pioneered several widely adopted portfolio strategies, including tactical asset allocation, global tactical asset allocation, tax-advantaged equity management, and the Fundamental Index™ approach to investing. His success in doing so has resulted in a reputation as one of the world's most provocative practitioners and respected financial analysts.

Rob has published more than 150 articles in publications including the Journal of Portfolio Management, Harvard Business Review, and Financial Analysts Journal, where he served as editor in chief from 2002 to 2006. He has received eight Graham and Dodd Scrolls, which are awarded annually from CFA Institute to the top Financial Analysts Journal articles of the year. He has also received four Bernstein Fabozzi/Jacobs Levy awards from the Journal of Portfolio Management. In 2013, Rob received the William F. Sharpe Indexing Lifetime Achievement Award, and in 2025 he received the ETF.com Lifetime Achievement Award. He is co-author of The Fundamental Index: A Better Way to Invest (Wiley 2008).

Rob received his Bachelor of Science summa cum laude in economics, applied mathematics, and computer science from the University of California, Santa Barbara.