Sal Arnuk

Sal Arnuk co-founded Themis Trading with Joe Saluzzi in 2002, operating as an agency equity broker focused on obtaining genuine best execution for institutional clients. Together with Saluzzi, he co-authored "Broken Markets: How High Frequency Trading and Predatory Practices on Wall Street Are Destroying Investor Confidence and Your Portfolio" (2012). The book and their accompanying white papers were among the earliest systematic critiques of payment for order flow, dark pools, and HFT advantages. Arnuk has testified before regulators and continues to comment on market structure through Themis's blog. His advocacy for institutional investor interests against structural advantages embedded in market microstructure predated Michael Lewis's "Flash Boys" by several years, establishing Themis as an early voice that shaped the terms of the HFT debate before it became widely understood in mainstream financial and regulatory discourse.