Matthew B. Management, Inc. is run by Leslie Seff, who is the former founder and manager of the NASDAQ Trading Department of Fidelity Investments. He has provided consulting or expert advice in numerous high profile cases, as a trading consultant or expert witness. Along those lines, he was the only trading expert to provide pre trial verbal testimony in the disputed merger between Archipelago and the New York Stock Exchange, where he provided expert testimony on behalf of the dissenting New York Stock Exchange seat holders.