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Callan G. Stein

Callan G. Stein


Boston, MA
Phone: 617.204.5103    Fax: 617.204.5150

Callan G. Stein is a partner in the Health Sciences Department and the White Collar Litigation and Investigations Practice Group of Pepper Hamilton LLP, resident in the Boston office. Mr. Stein has a broad litigation and investigation practice, focusing on white collar criminal matters, corporate and commercial civil litigation, internal investigations and health care litigation.

Mr. Stein’s primary goal when working with his clients is to help them avoid litigation, government enforcement actions, and other disputes by developing and implementing risk mitigation strategies. These strategies include implementing, updating, and enhancing corporate compliance programs, and helping clients investigate complaints and other issues raised internally before they ripen into litigation or result in whistleblower allegations. When conducting internal investigations for corporate clients, Mr. Stein guides clients through the investigative process, using his in-depth knowledge of how prosecutors and regulators approach such allegations, to investigate allegations and advise clients on the most complex and sensitive issues.

When litigation and government investigations do occur, Mr. Stein defends clients in those matters. He is experienced representing clients in the health care industry during criminal investigations, including against allegations involving the False Claims Act, the Anti-Kickback Statute, Stark Law and other health care fraud and abuse laws and regulations. Mr. Stein also represents clients in non-health care investigations involving securities fraud, mail and wire fraud, racketeering and RICO violations, export control laws such as ITAR and EAR, and violations of food and drug laws such as the Food, Drug and Cosmetic Act. Mr. Stein defends companies and individuals during all stages of the investigation process, including responding to government requests for information that typically signal an active or potential investigation, such as HIPAA subpoenas, administrative subpoenas, civil investigative demands, grand jury subpoenas or search warrants.

Mr. Stein is also an experienced commercial and civil litigator, and he has a particular focus in health care litigation. Mr. Stein represents health care providers in civil and regulatory enforcement actions alleging fraud and abuse, including Medicare, Medicaid and fraud claims by other government and third-party payors. Mr. Stein also represents hospitals, health care facilities, providers, practices and medical staffs in litigation arising from payor disputes, utilization review management issues, and medical staff credentialing and privilege disputes. As part of his health care litigation practice, Mr. Stein has represented health care facilities and other health care employers in employment-related litigation alleging violations of state and federal health care whistleblower laws and physician disciplinary matters.

Before joining Pepper, Mr. Stein was a partner at Barrett & Singal.


  • J.D., Boston University School of Law, 2007
  • B.A., cum laude, Brandeis University, 2004

Bar Admissions

  • Massachusetts
  • Rhode Island

Court Admissions

  • U.S. District Court, District of Massachusetts
  • U.S. Court of Appeals, First Circuit

Practice Areas

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