Christine M. Hammer

Certified Public Accountant;
Senior Advisor, Cornerstone Research

For more information, contact:

  • Kostis Hatzitaskos
  • Russell Molter

or any member of our senior staff.


Christine Hammer is a certified public accountant with expertise in cost accounting, intellectual property, and lost profits. She specializes in applying accounting and economic theory to issues arising in business litigation. Her work most often involves assessing complex cost allocations, “but-for” cost and profit estimates, and alternative damages analyses.

Antitrust and competition

In the area of antitrust and competition, Ms. Hammer has addressed issues related to merger efficiencies, predatory pricing claims, and lost profit damages in industries such as pharmaceuticals, healthcare, telecommunications equipment, and coal slurry pipelines. She has served as an expert in cases involving anticompetitive practice allegations under both U.S. federal and California law. Ms. Hammer testified as the U.S. government’s efficiencies expert in the proposed $37 billion merger between health insurers Aetna and Humana.

Intellectual property

Ms. Hammer has provided expert testimony in intellectual property matters involving infringement of patents, trademarks, and copyrights. She has testified in cases related to several industries, including software, computer hardware, search engines, medical devices, telecommunications, and other consumer products.

General business litigation

In other litigation matters, Ms. Hammer has testified on damages, loss causation, and cost analyses. These cases include issues related to the earn-out provisions of a contract, lost revenue from a federal land acquisition, and mutual fund profitability.


United States v. Bertelsmann Se & Co. KGaA et al.


In the Matter of Walgreens Boots Alliance and Rite Aid


In the Matter of Otto Bock HealthCare North America Inc.


Proposed Merger of Aetna and Humana Enjoined


In re Actiq Sales and Marketing Practices Litigation


Auditor Liability Following Client Bankruptcy


Copyright Infringement of Design of Cellular Telephone Retail Stores


Baker v. American Century Investment Management, Inc.

  • “Efficiencies in Healthcare Mergers: Perspectives on Recent Challenges and the Path Ahead,” American Bar Association, 16 December 2021