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Mark Seifert - Brunswick Group. Washington, DC, US

Mark Seifert

Partner, Washington, D.C. | Brunswick Group


Mark Seifert offers insights and practical advice to clients addressing complex privacy issues.


Answers (1)

Can cybersecurity breaches threaten deal valuations?

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Investors sharply reduce their post-close valuations of companies that have completed acquisitions when data breaches are revealed, according to a new survey of investors and analysts by Brunswick Group, a global critical issues advisory firm.Brunswick’s third annual Data Valuation Survey also found that investors raise their post-deal valuations for companies that have demonstrated preparation for cybersecurity issues.Brunswick Group investor survey finds post-close M&A valuations cut by data breachesMost investors say they would lower post-close valuation if either party had a breachHalf of surveyed investors would award higher valuation for companies working with security firms to reduce potential cyber risks






How to Earn the Data Premium Should Competence In Data Security Be An Ethical Obligation For Law Firms? | Cy-pher What Do You Do With A Hacked Law Firm? | Cy-pher




Mark Seifert co-chairs the global Cybersecurity and Privacy practice, helping clients prepare for and respond to cybersecurity incidents. A certified privacy professional and a former regulatory attorney, Mark offers insights and practical advice to clients addressing complex privacy issues. In addition to his work in cybersecurity and privacy, he also advises clients on a variety of matters including corporate communications, media relationships, thought leadership, and government affairs.

Mark has extensive experience within the US government, including 16 years with the Federal Communications Commission as well as service in all three branches of government. At the Department of Commerce, he oversaw a $5bn broadband infrastructure program. Mark also served as counsel to the House Committee on Energy and Commerce on telecommunications and technology matters.

Mark Siefert has led retained accounts, projects, and transactions with both public and privately-owned clients including AT&T, Facebook, GE, Abbott, and Southwest. He also serves as a board member for the Center for Democracy and Technology.

Areas of Expertise (7)


Media Relations

Cyber Security


Privacy and Data Management

Thought Leadership

Broadband Technology

Education (2)

University of Virginia: J.D., Law 1991

Birmingham-Southern College: B.A., Pre-Medicine/Music 1984

Media Appearances (1)

Pride Without Parades: What the Fight for LGBTQ+ Inclusion Means in 2020

Triple Pundit  


Mark Seifert, an openly gay partner at Brunswick Group and co-chair of the firm's cybersecurity and privacy practice, encouraged business leaders to seize the moment of COVID-19 lockdowns and attention on racial justice as an entry point to push for greater equality: "If ever there was a time to challenge preconceived notions and challenge the current state, it's now," he said. "It's now when we're all fighting a virus. It's now when we are taking a serious look at our relationship with the Black community. Let's rip off some of the old stuff and start anew."

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Articles (3)

2016 Global data valuation survey

| Brunswick Group Perspectives (2016)

The survey results, which reflect the views of 208 buy-side investors and sell-side analysts across the US, UK, Europe, and Asia, offered good news for companies taking steps to address cybersecurity issues.

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Cybersecurity introduction

| Brunswick Group Perspectives (2016)

Cyber threats are generating some scary statistics: $400 billion a year in losses from attacks, with some larger businesses experiencing more than 12,000 attacks each year. But there is also good news. Companies are recognizing that cybersecurity is not a technology concern but rather a critical business issue and one they are preparing to deal with.

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Unclear but present danger

| Brunswick Group Perspectives (2016)

Security technology company McAfee has reported that its “malware zoo” – where it logs all the malicious software, or malware, it discovers – has grown at last count to 433 million species, around 70 percent more than the previous year.

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