John W.Mazzeo
Counsel
Immigration
jmazzeo@seyfarth.com
John crafts and implements pragmatic solutions to complex legal issues in immigration compliance and worksite enforcement—one of the most consequential areas of corporate risk today.
More About John
Enterprise immigration compliance and employment eligibility verification are essential for business continuity, growth, and risk mitigation. Companies of all sizes are subject to strict federal—and sometimes state—regulatory requirements and obligations, regardless of whether they employ any foreign nationals. John works with employers to address legal risk thoughtfully, balancing compliance goals with business and operational realities.
John combines his years of experience as an ICE trial attorney focusing on worksite enforcement with his years counseling one of the nation’s largest providers of onboarding services and solutions to craft practical solutions that simultaneously mitigate risk and promote growth. John has a unique and rare ability to understand both the legal and operational issues inherent with employment eligibility verification and immigration compliance.
John combines his years of experience as an ICE trial attorney focusing on worksite enforcement with his years counseling one of the nation’s largest providers of onboarding services and solutions to craft practical solutions that simultaneously mitigate risk and promote growth. John has a unique and rare ability to understand both the legal and operational issues inherent with employment eligibility verification and immigration compliance.
- JD, Drexel University Thomas R. Kline School of Law
- BA, Ursinus College
- Not admitted to practice in the District of Columbia. Practice limited to immigration and nationality law.
- Pennsylvania
- Pennsylvania Supreme Court
Related Services
Related News & Insights
-
Speaking Engagement
Jun 20, 2026
John Mazzeo to Speak at 2026 AILA Annual Conference
-
Legal Update
Jun 18, 2026
USCIS Expands AR-11 (Change of Address Form): Elevates Employer Exposure
-
Speaking Engagement
Jun 16-19, 2026
John Mazzeo to Present Two Sessions at SHRM 2026
-
Media Mentions
Jun 8, 2026
Bloomberg Law Quotes John Mazzeo on Proposed E‑Verify Expansion
- American Immigration Lawyers Association, member (2021-present), Verification and Documentation Liaison Committee, member (2023-present), and Vice Chair (2024-present)
- Association of Corporate Counsel (International), member (2021-2026), Corporate and Securities Law Network, member (2022-2026), Vice Chair (2024-2025), and Chair (2025-2026)
- Association of Corporate Counsel (Greater Philadelphia), member (2021-2026), International Law Section, Practice Area Network Chair (2024-2025)
- Law360 Editorial Board, Immigration (2023-2025)
- Co-Author, "California Compliance Refresher: Immigration Enforcement Without the Missteps or Miscalculations," Legal Update, Seyfarth Shaw LLP (June 4, 2026)
- Co-Author, “Adjustment Ambiguity: What Employers Should Know About USCIS’s New Policy Direction,” Legal Update, Seyfarth Shaw LLP (May 26, 2026)
- Co-Author, "Immigration Due Diligence: A Core Requirement in Corporate Transactions," Business Law Today (March 2026)
- Author, "Form I-9 Compliance: Adapting and Thriving in an Era of Enhanced Enforcement," HR Florida Newswire (February 2025)
- Co-Author, "Why Direct Student-Athlete Payments Create an Immigration Crisis for Universities," Athletic Director University (February 11, 2025)
- Author, "Form I-9 and E-Verify: Not Just an HR Function Any Longer," ACC Docket (February 5, 2024)
- Author, "Video Enabled: Evaluating New I-9 Compliance Procedures," HR Pulse, American Society for Healthcare Human Resources Administration (Winter 2023)
- Co-Author, "Demystifying Employment Authorization under TPS," American Immigration Lawyers Association (December 11, 2023)
- Co-Author, “Restrictions and Guidance on the Use of Authorized Representatives in California for Purposes of Completing Form I-9,” American Immigration Lawyers Association (November 10, 2023)
- Author, “Don’t Get ‘Chomped’: Employers Must Be Aware of Employment Verification Requirements,” HR Florida Newswire,(August 2023)
- Panelist, "Form I-9 and E-Verify Under Scrutiny: Avoiding Compliance Pitfalls and Discrimination Liability," American Immigration Lawyers Association Annual Conference (June 20, 2026)
- Speaker, "Employers in the Hot Seat: Surviving Form I-9 Audits and Enforcement in Trump 2.0," Society for Human Resource Management Annual Conference (June 18, 2026)
- Speaker, "The Bigger Picture: A Worksite Compliance Strategy for Small and Mid-Size Employers," Society for Human Resource Management Annual Conference (June 18, 2026)
- Speaker, "Compliance Chaos: I-9, E-Verify, and Workforce Continuity in 2026," Society for Human Resource Management Annual Conference (June 17, 2026)
- Speaker, "Leveraging Biometric Identity Verification to Mitigate Enterprise Identity Fraud," Secure Technology Alliance Identity and Access Forum (March 3, 2026)
- Panelist, "Immigration Raids, Work Visas, and What Labor and Employment Lawyers Need to Know," Webinar, American Bar Association (February 12, 2026)
- Panelist, "The Resurgence of Worksite Enforcement," American Immigration Lawyers Association - New York Chapter (December 1, 2025)
- Panelist, "Immigration 2025 Spotlight: Acute Risks of Immigration Raids and What to Expect in the Near-to-Mid-Term," American Bar Association Labor and Employment Law Section Conference (November 14, 2025)
- Panelist, "Paper Cuts to Prison Time: How Form I-9 Mistakes Become Legal Nightmares," American Immigration Lawyers Association - Ohio Chapter (October 17, 2025)
- Panelist, "From Disruption to Strategy: Tackling Immigration Challenges in a Changing Landscape," HR Florida (August 26, 2025)
- Speaker, "Navigating the New Immigration Landscape: Preparing Employers for Enhanced Audits and Work Authorization Challenges," Society for Human Resource Management Annual Conference (June 30, 2025)
- Panelist, "Verification and Documentation Roundtable," American Immigration Lawyers Association Spring Conference (April 3, 2025)
- Speaker, "Disruption! Preparing Clients and Their Employees for Worksite Enforcement Operations During the Second Trump Administration," American Immigration Lawyers Association Roundtable (December 13, 2024)
- Speaker, "Form I-9 Uncovered: Unlocking Compliance Through Multiple Completion Methods," HR Florida Annual Conference (August 26, 2024)
- Speaker, "Form I-9 in a Post-COVID World," Annual Meeting, American Society for Healthcare Human Resources Administration (April 26, 2022)
John crafts and implements pragmatic solutions to complex legal issues in immigration compliance and worksite enforcement—one of the most consequential areas of corporate risk today.
More About John
Enterprise immigration compliance and employment eligibility verification are essential for business continuity, growth, and risk mitigation. Companies of all sizes are subject to strict federal—and sometimes state—regulatory requirements and obligations, regardless of whether they employ any foreign nationals. John works with employers to address legal risk thoughtfully, balancing compliance goals with business and operational realities.
John combines his years of experience as an ICE trial attorney focusing on worksite enforcement with his years counseling one of the nation’s largest providers of onboarding services and solutions to craft practical solutions that simultaneously mitigate risk and promote growth. John has a unique and rare ability to understand both the legal and operational issues inherent with employment eligibility verification and immigration compliance.
John combines his years of experience as an ICE trial attorney focusing on worksite enforcement with his years counseling one of the nation’s largest providers of onboarding services and solutions to craft practical solutions that simultaneously mitigate risk and promote growth. John has a unique and rare ability to understand both the legal and operational issues inherent with employment eligibility verification and immigration compliance.
- JD, Drexel University Thomas R. Kline School of Law
- BA, Ursinus College
- Not admitted to practice in the District of Columbia. Practice limited to immigration and nationality law.
- Pennsylvania
- Pennsylvania Supreme Court
Related Services
Related News & Insights
-
Speaking Engagement
Jun 20, 2026
John Mazzeo to Speak at 2026 AILA Annual Conference
-
Legal Update
Jun 18, 2026
USCIS Expands AR-11 (Change of Address Form): Elevates Employer Exposure
-
Speaking Engagement
Jun 16-19, 2026
John Mazzeo to Present Two Sessions at SHRM 2026
-
Media Mentions
Jun 8, 2026
Bloomberg Law Quotes John Mazzeo on Proposed E‑Verify Expansion
- American Immigration Lawyers Association, member (2021-present), Verification and Documentation Liaison Committee, member (2023-present), and Vice Chair (2024-present)
- Association of Corporate Counsel (International), member (2021-2026), Corporate and Securities Law Network, member (2022-2026), Vice Chair (2024-2025), and Chair (2025-2026)
- Association of Corporate Counsel (Greater Philadelphia), member (2021-2026), International Law Section, Practice Area Network Chair (2024-2025)
- Law360 Editorial Board, Immigration (2023-2025)
- Co-Author, "California Compliance Refresher: Immigration Enforcement Without the Missteps or Miscalculations," Legal Update, Seyfarth Shaw LLP (June 4, 2026)
- Co-Author, “Adjustment Ambiguity: What Employers Should Know About USCIS’s New Policy Direction,” Legal Update, Seyfarth Shaw LLP (May 26, 2026)
- Co-Author, "Immigration Due Diligence: A Core Requirement in Corporate Transactions," Business Law Today (March 2026)
- Author, "Form I-9 Compliance: Adapting and Thriving in an Era of Enhanced Enforcement," HR Florida Newswire (February 2025)
- Co-Author, "Why Direct Student-Athlete Payments Create an Immigration Crisis for Universities," Athletic Director University (February 11, 2025)
- Author, "Form I-9 and E-Verify: Not Just an HR Function Any Longer," ACC Docket (February 5, 2024)
- Author, "Video Enabled: Evaluating New I-9 Compliance Procedures," HR Pulse, American Society for Healthcare Human Resources Administration (Winter 2023)
- Co-Author, "Demystifying Employment Authorization under TPS," American Immigration Lawyers Association (December 11, 2023)
- Co-Author, “Restrictions and Guidance on the Use of Authorized Representatives in California for Purposes of Completing Form I-9,” American Immigration Lawyers Association (November 10, 2023)
- Author, “Don’t Get ‘Chomped’: Employers Must Be Aware of Employment Verification Requirements,” HR Florida Newswire,(August 2023)
- Panelist, "Form I-9 and E-Verify Under Scrutiny: Avoiding Compliance Pitfalls and Discrimination Liability," American Immigration Lawyers Association Annual Conference (June 20, 2026)
- Speaker, "Employers in the Hot Seat: Surviving Form I-9 Audits and Enforcement in Trump 2.0," Society for Human Resource Management Annual Conference (June 18, 2026)
- Speaker, "The Bigger Picture: A Worksite Compliance Strategy for Small and Mid-Size Employers," Society for Human Resource Management Annual Conference (June 18, 2026)
- Speaker, "Compliance Chaos: I-9, E-Verify, and Workforce Continuity in 2026," Society for Human Resource Management Annual Conference (June 17, 2026)
- Speaker, "Leveraging Biometric Identity Verification to Mitigate Enterprise Identity Fraud," Secure Technology Alliance Identity and Access Forum (March 3, 2026)
- Panelist, "Immigration Raids, Work Visas, and What Labor and Employment Lawyers Need to Know," Webinar, American Bar Association (February 12, 2026)
- Panelist, "The Resurgence of Worksite Enforcement," American Immigration Lawyers Association - New York Chapter (December 1, 2025)
- Panelist, "Immigration 2025 Spotlight: Acute Risks of Immigration Raids and What to Expect in the Near-to-Mid-Term," American Bar Association Labor and Employment Law Section Conference (November 14, 2025)
- Panelist, "Paper Cuts to Prison Time: How Form I-9 Mistakes Become Legal Nightmares," American Immigration Lawyers Association - Ohio Chapter (October 17, 2025)
- Panelist, "From Disruption to Strategy: Tackling Immigration Challenges in a Changing Landscape," HR Florida (August 26, 2025)
- Speaker, "Navigating the New Immigration Landscape: Preparing Employers for Enhanced Audits and Work Authorization Challenges," Society for Human Resource Management Annual Conference (June 30, 2025)
- Panelist, "Verification and Documentation Roundtable," American Immigration Lawyers Association Spring Conference (April 3, 2025)
- Speaker, "Disruption! Preparing Clients and Their Employees for Worksite Enforcement Operations During the Second Trump Administration," American Immigration Lawyers Association Roundtable (December 13, 2024)
- Speaker, "Form I-9 Uncovered: Unlocking Compliance Through Multiple Completion Methods," HR Florida Annual Conference (August 26, 2024)
- Speaker, "Form I-9 in a Post-COVID World," Annual Meeting, American Society for Healthcare Human Resources Administration (April 26, 2022)