Experienced Controlled Substance Regulatory Advisor Linden Barber Rejoins Quarles as Health & Life Sciences Partner
November 12, 2025 (Indianapolis) -- The national law firm of Quarles & Brady LLP announced today that Linden Barber, who has deep experience across government, in-house and private practice roles advising on controlled substance regulatory matters at the federal and state level, has joined the firm’s Indianapolis office as a partner in the Health & Life Sciences Practice Group.
Previously a partner at Quarles from 2011-2017, Barber rejoins the firm after serving as executive vice president, quality and regulatory affairs and chief regulatory counsel at Cardinal Health. Prior to his initial stint at Quarles, he was the head of the U.S. Drug Enforcement Administration’s (DEA) enforcement litigation section.
Barber counsels an array of health care companies, organizations and practitioners on DEA regulatory matters, as well as a broad range of compliance and enforcement issues involving the Controlled Substances Act (CSA) and state-controlled substances laws and regulations. He represents clients in DEA administrative actions, civil penalty matters and Board of Pharmacy proceedings, and also provides guidance on the design, implementation and operation of systems to facilitate compliance with federal and state-controlled substances laws and regulations.
“With his impressive breadth of experience and reputation as a thought leader on controlled substance regulation, Linden will be a tremendous resource to our clients,” said Brenda Maloney Shafer, national chair of the Health & Life Sciences Practice Group. “We’re thrilled he’s returning to Quarles, not just because of the value to our clients but also because of his ability to mentor younger attorneys throughout our group and the firm.”
Barber’s clients include manufacturers, wholesale distributors, pharmacies, hospitals and individual practitioners relating to their obligations under CSA and DEA's regulations, and registrants in administrative and civil litigation matters in actions brought under the CSA.
A veteran of the U.S. Army, he served as judge advocate for the Army with assignments as a prosecutor, defense counsel and legal advisor to the National Security Agency, the Army’s military intelligence brigade in Korea, and a corps support group in Iraq. Barber received a Bronze Star and Combat Action Badge for service in Operation Iraqi Freedom.
He earned his B.A. from Tennessee Temple University and J.D. from University of Notre Dame Law School.
“My colleagues at Quarles are invested in the success of our clients and innovative in solving complex legal problems,” Barber said. “I returned to Quarles because of the people at the firm with whom I have the privilege to serve our clients.”