David F. Marcus

Senior Vice President


  • Boston


David Marcus has more than twenty-five years of experience providing consulting services and expert testimony in litigation involving economic and financial issues. His primary areas of focus are securities litigation, valuation, cases involving financial institutions, and white collar litigation. Dr. Marcus serves on Cornerstone Research’s board of directors, and is a former head of both the firm’s finance practice and its Boston office. His research has been published in the Journal of Financial Economics.

Securities litigation
  • Analyzed the factors affecting publicly traded securities prices
  • Evaluated whether securities traded in efficient markets
  • Examined whether information had an impact on securities prices
  • Evaluated whether investor losses were the result of alleged misstatements and omissions
  • Evaluated measures for determining per share inflation and class wide damages
  • Researched the value of corporate control and voting rights on stock prices
  • Evaluated disputes over business enterprise values following mergers and acquisitions
  • Modeled lost future income related to product liability issues
  • Estimated lost profits from alleged breach of contract
  • Analyzed the value of complex derivative securities
Financial institutions
  • Analyzed management fees charged to mutual fund shareholders
  • Assessed allegations of market manipulation in thinly traded financial instruments
  • Analyzed the financial impact of alleged index manipulation
  • Analyzed markups charged on foreign exchange transactions
  • Evaluated the reasonableness of hedging strategies
  • Assessed whether investors received best execution on stock transactions
  • Researched factors associated with IPO allocations
  • Analyzed capital market transactions
White collar litigation
  • Assessed materiality and damages in SEC actions and criminal matters
  • Analyzed materiality, trading strategies and damages in insider trading cases
  • Evaluated the effect of alleged market manipulation schemes on securities prices
  • Assessed stock price movements following alleged pump-and-dump schemes
  • Assessed damages in cases involving alleged Ponzi schemes
  • Analyzed loss causation in criminal securities cases
Press Release

WWL Expert Witnesses: Commercial Litigation 2022


Cornerstone Research Connects: 2019 Securities Class Action Settlements


Mooney et al. v. Diversified Business Communications et al.


Regulatory Investigation Pertaining to Losses Incurred by a Hedge Fund


Appraisal Litigation in a Going Private Transaction


Kennis v. Metropolitan West Asset Management LLC


Firefighters’ Retirement System et al. v. Citco Group et al.


Appraisal Litigation in Delaware—Trends in Petitions and Opinions, 2006–2018

  • “The Changing Nature of SEC Enforcement Actions,” Law360, October 2013
  • “The Future of SEC Enforcement,” Law360, April 2013
  • “An Imprecise Measure of Loss—At Best,” Law360, June 2012
  • “The Increasing Importance of Loss Causation Analysis,” Law360, October 2011