Mark A. Williams

Counsel in St. Louis, MO

Mark joined Sandberg Phoenix in 2024 as an attorney in the firm’s Business practice group. He provides companies with strategic legal and business advice concerning data, privacy, and cybersecurity issues.  He has advised companies large and small, from the Fortune 10 to startups, on issues related to compliance, incident response, investigations, and transactions.  Mark prides himself on developing creative solutions that minimize risk and protect his client’s interests.

Mark works with companies and organizations to reduce risks associated with data privacy and cybersecurity regulations, including the California Consumer Privacy Act (CCPA), the New York Department of Financial Services Cybersecurity Regulation (NYCRR 500), the Health Insurance Portability and Accountability Act (HIPAA), the Telephone Consumer Protection Act (TCPA), the Children’s Online Privacy Protection Act (COPPA), and foreign laws like the EU General Data Protection Regulation (GDPR).

Mark has successfully represented companies in investigations brought by American and European regulators addressing data practices and competition issues related to the collection and use of data. He also has advised companies on sales, acquisitions, and other transactions, including data privacy issues related to licensing and distressed sales.  Mark also assists companies in responding to security incidents, including by overseeing forensic investigations, engaging with regulators, and assessing legal obligations and risk.

Mark is a Certified Information Privacy Professional (CIPP/US).

Outside of work, Mark is committed to bettering his community through volunteerism and local civic engagement. 


Data, Privacy, and Cybersecurity Intellectual Property Litigation Corporate Formation, Governance & Advice Corporate Transactions Mergers & Acquisitions Securities


Automotive Aviation Banking & Finance Brokers / Dealers & Financial Advisors Consumer Products Entrepreneurs, Closely Held & Family Owned Business Hospitals Long-term Care & Senior Living Manufacturing & Distribution Mortgage Providers & Services Physicians & Allied Health Professionals Wholesale & Retail Services