William Diaz

Senior Manager

William Diaz

William Diaz
William Diaz
  • People

Senior Manager

William Diaz

Country / Territory

  • United KingdomUnited Kingdom

Get in touch

Languages

  • English

Contact information

Email

[email protected]

T:+44 (0)207 090 9272

F:+44 (0)207 090 9101

London

Fragomen LLP

1st Floor, 95 Gresham St,

London EC2V 7NA

United Kingdom

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Get in touch

Languages

  • English

Contact information

Email

[email protected]

T:+44 (0)207 090 9272

F:+44 (0)207 090 9101

London

Fragomen LLP

1st Floor, 95 Gresham St,

London EC2V 7NA

United Kingdom

Connect via Linkedin

Get in touch

Languages

  • English

Contact information

Email

[email protected]

T:+44 (0)207 090 9272

F:+44 (0)207 090 9101

London

Fragomen LLP

1st Floor, 95 Gresham St,

London EC2V 7NA

United Kingdom

Connect via Linkedin
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William is a Senior Manager based in Fragomen’s London office. He assists clients in a variety of industries including finance, technology and entertainment, with a particular emphasis on assisting with complex consular filing for treaty investors, intracompany transferees and individuals of extraordinary ability.

William frequently advises small and medium-sized enterprises throughout the EMEA region in expanding to the U.S. and transferring key personnel. These clients range from start-ups to long established businesses across a range of professions. 

He has previously volunteered with various organisations, including a civil liberties non-profit and an international criminal tribunal. 

Education

  • Leiden University, LL.M., 2011
  • Pace University School of Law, J.D., 2009
  • Fordham University, B.A., 2005

More from William

Admissions

Immigration Credentials: Registered Attorney with the United States Department of Justice’s Executive Office for Immigration Review, 2013-present

Bar Admissions: New York State

Professional accomplishments

Member, American Immigration Lawyers Association (AILA)

Former Member, AILA CBP Liaison Committee

Experience

Obtained a nonimmigrant waiver of inadmissibility for a noted entertainer with previous criminal convictions.

Advised a multinational vehicle manufacturer in transferring key managerial and technical personnel for the expansion of their U.S. operations.

Helped a search engine provider with a complex business ownership structure acquire E-2 company registration and transfer key managers and executives to the United States.

Devised strategies to ensure a television production company could transfer key talent on an expedited basis during a period of prolonged global disruption in U.S. visa issuance.

Advised a start-up technology marketing firm and guided U.S. expansion strategy to support treaty investor visas for key managerial and specialist personnel.

Publications and lectures

Author, “Leading Britain’s Conversation: One Old Arrest Can Stop You Entering the USA, Even If You Were Never Convicted.” Fragomen, 16 March 2026.

Author, “Tightening immigration rules will impact the games industry in 2026.” Games Industry, 6 February 2026.

Author, “Games Industry: US H-1B Visas: Alternatives to a $100,000 Fee.” Fragomen, 29 October 2025.

Author, “Tech and Global Mobility: The impact of the new US Administration.” Computer Weekly, 4 March 2025.

Panelist, “Bobbing for Visas: Alternative Uses for the B Visa Category.” AILA Rome District Chapter Fall Conference 2023, London, UK, October 2023.

Presenter, “US Growth Programme: Visas for investment and expansion.” TechNation US Growth Workshop 3.0, London, UK, September 2022.

Panelist, “Ch-Ch-Changes: Regulatory, Policy, and Adjudications.” AILA National Conference 2020, Webinar, July 2020.

Presenter, “US Visas for Irish Investors.” Dublin Chamber of Commerce, Dublin, Ireland, February 2020.

Presenter, “Obtaining the Right Visas.” UK Department of International Trade, Cambridge, UK, October 2019.

Presenter, “Visa for US expansion.” Fingal Dublin Chamber, Dublin, Ireland, February 2019.

Presenter, “US Immigration for Investors.” South West World Trade Summit, Bristol, UK, July 2018.

Presenter, “US Immigration for Latvian Investors.” Gateway to the USA Program, Riga, Latvia, May 2018.

Panelist, “Humanitarian Options of Last Resort.” AILA National Conference 2017, New Orleans, Louisiana, June 2017.

Co-author, “Humanitarian Options of Last Resort.” AILA Immigration Practice Pointers (2017-18 Ed.), Pages 575-585, 2017.

Panelist, “Advanced E Visas.” AILA Rome District Chapter Fall Conference 2016, Amsterdam, Netherlands, October 2016.

Author, “Common US immigration consequences of mergers and acquisitions.” Human Resource Management International Digest, Volume 23, Issue 7 (2015). Print and web.

Author, “Want to work in the US? The secret to securing a successful application.” The Stage, September 25, 2015. Web.

Author, “Global Mobility Strategies for SMEs Expanding to the US.” Corporate Vision Magazine, August 2015: 42-43. Print and web.

Author, “From Posting to Permanent Residency.” Global: The International Briefing, December 2015: 40-41. Print and web.

Author, “Transferring Professional Athletes to the U.S.” HRreview, July 10, 2015. Web.

Author, “US visa eligibility: five HR issues when transferring employees.” Personnel Today, August 28, 2015. Web.

Panelist, "Legal IT Roundtable." Roundtable event, The Law Society Gazette, London, UK, July 2015.

Presenter, “US immigration for start-ups.” Presentation, Access to the US and the US Ignite Program, London, UK, June 2015.

Contributor, “Clarkson faced police interview over attack.” The Times, 27 March 2015.

Presenter, “US immigration overview.” Presentation, Techstars, London, UK, January 2015.

Author, “Dualist, but not Divergent: Evaluating United States Implementation of the 1267 Sanctions Regime.” Liberty University Law Review, Volume 5, Issue 3 (2011): 333-378. Print and web.

William’s insights

March 16, 2026 | Media mentions

Leading Britain's Conversation: One Old Arrest Can Stop You Entering the USA, Even If You Were Never ConvictedRead more

February 9, 2026 | Media mentions

Games Industry: Tightening Immigration Rules Will Impact the Games Industry in 2026Read more

October 29, 2025 | Media mentions

Games Industry: US H-1B Visas: Alternatives to a $100,000 FeeRead more
More related insights

William’s insights

March 16, 2026 | Media mentions

Leading Britain's Conversation: One Old Arrest Can Stop You Entering the USA, Even If You Were Never ConvictedRead more

February 9, 2026 | Media mentions

Games Industry: Tightening Immigration Rules Will Impact the Games Industry in 2026Read more

October 29, 2025 | Media mentions

Games Industry: US H-1B Visas: Alternatives to a $100,000 FeeRead more
More related insights

William’s insights

March 16, 2026 | Media mentions

Leading Britain's Conversation: One Old Arrest Can Stop You Entering the USA, Even If You Were Never ConvictedRead more

February 9, 2026 | Media mentions

Games Industry: Tightening Immigration Rules Will Impact the Games Industry in 2026Read more

October 29, 2025 | Media mentions

Games Industry: US H-1B Visas: Alternatives to a $100,000 FeeRead more
More related insights

Country / Territory

  • United KingdomUnited Kingdom

Get in touch

Languages

  • English

Contact information

Email

[email protected]

T:+44 (0)207 090 9272

F:+44 (0)207 090 9101

London

Fragomen LLP

1st Floor, 95 Gresham St,

London EC2V 7NA

United Kingdom

Connect via Linkedin

William’s insights

March 16, 2026 | Media mentions

Leading Britain's Conversation: One Old Arrest Can Stop You Entering the USA, Even If You Were Never ConvictedRead more

February 9, 2026 | Media mentions

Games Industry: Tightening Immigration Rules Will Impact the Games Industry in 2026Read more

October 29, 2025 | Media mentions

Games Industry: US H-1B Visas: Alternatives to a $100,000 FeeRead more
More related insights

Share

  • Twitter
  • Facebook
  • LinkedIn

Share

  • Twitter
  • Facebook
  • LinkedIn

Get in touch

Languages

  • English

Contact information

Email

[email protected]

T:+44 (0)207 090 9272

F:+44 (0)207 090 9101

London

Fragomen LLP

1st Floor, 95 Gresham St,

London EC2V 7NA

United Kingdom

Connect via Linkedin

William’s insights

March 16, 2026 | Media mentions

Leading Britain's Conversation: One Old Arrest Can Stop You Entering the USA, Even If You Were Never ConvictedRead more

February 9, 2026 | Media mentions

Games Industry: Tightening Immigration Rules Will Impact the Games Industry in 2026Read more

October 29, 2025 | Media mentions

Games Industry: US H-1B Visas: Alternatives to a $100,000 FeeRead more
More related insights

Share

  • Twitter
  • Facebook
  • LinkedIn

Share

  • Twitter
  • Facebook
  • LinkedIn

Get in touch

Languages

  • English

Contact information

Email

[email protected]

T:+44 (0)207 090 9272

F:+44 (0)207 090 9101

London

Fragomen LLP

1st Floor, 95 Gresham St,

London EC2V 7NA

United Kingdom

Connect via Linkedin

William’s insights

March 16, 2026 | Media mentions

Leading Britain's Conversation: One Old Arrest Can Stop You Entering the USA, Even If You Were Never ConvictedRead more

February 9, 2026 | Media mentions

Games Industry: Tightening Immigration Rules Will Impact the Games Industry in 2026Read more

October 29, 2025 | Media mentions

Games Industry: US H-1B Visas: Alternatives to a $100,000 FeeRead more
More related insights

Share

  • Twitter
  • Facebook
  • LinkedIn

Share

  • Twitter
  • Facebook
  • LinkedIn

Explore more at Fragomen

Media mentions

The PIE: Canada Fraud Case Exposes “Acute” Sector Integrity Issues

Partner Jack Kim discusses how fraud has shaped Canada's international student reforms and ongoing integrity efforts.

Learn more

Blog post

Skilled Worker Salary Changes: What Employers Need to Know

In this blog, Senior Associate Charlotte Roberts explains what these changes mean for employers, why salary discounts may no longer be a reliable long-term strategy and how early workforce planning can help businesses continue to access international talent while managing compliance and costs.

Learn more

Media mentions

Markt und Mittelstand: EU-Entsendung: Diese Fehler kosten Unternehmen bis zu 500.000 Euro

Senior Associate Isabel Schnitzler outlines the key compliance considerations for employers with employees working across the EU.

Learn more

Podcast

Reality Check Pt. 3: Immigration Law in Pop Culture

Associates Julia Manacher and Stephanie Weaver examine immigration issues emerging in a popular reality television series, including K-1 visa denials, consular non-reviewability, fraud findings and changing adjudication policies.

Learn more

Blog post

Separating Fact and Fiction: Debunking Myths in German Citizenship Law

Manager Dr. Adela Schmidt examines common misconceptions in German citizenship law, including birthright citizenship, dual citizenship, citizenship by descent and naturalization processing, and explains why eligibility often depends on specific legal requirements, timelines and documentation.

Learn more

Awards

Fragomen Professionals Named 2026 TLC Lions Human Awards Americas Finalists

Partner Audrea Golding, Senior Associate Kyle Sommer and Senior Talent Development Director Wendy Milici have been named finalists in the 2026 TLC Lions Human Awards Americas, recognizing their contributions to human-centered leadership, workplace culture and inclusion.

Learn more

Media mentions

Biometric Update: Fragomen and SICPA Form JV to Join Digital Identity Market With End-to-End Platform

Fragomen and SICPA have launched a global joint venture to develop an end-to-end digital identity platform that enables secure identity verification, document authentication and verifiable credential management.

Learn more

Media mentions

Times of India: Trump Administration Eyes Tighter H-1B, Green Card and Student Visa Rules; Indians Could Be Among Most Affected

Senior Counsel Mitch Wexler discusses how potential changes to H-1B visas, employment-based green cards and OPT could impact employers’ workforce planning and compliance obligations.

Learn more

Media mentions

World Business Travel Forum: Leaders in Motion - Middle East Mobility and Travel Resilience

In a Leaders in Motion interview with World Business Travel Forum, Partner Ali Haider and Nomadic CEO Carsten Østberg discuss recent travel and mobility developments across the Middle East and practical considerations for employers managing cross-border talent in the region.

Learn more

Media mentions

Global Mobility Lawyer: Dairy Industry Gains Clarity on H-2A Guest Worker Eligibility

Partner Rachel Beardsley explains how new DHS guidance clarifies that dairy employers may use the H-2A program when they can demonstrate a temporary or seasonal labor need.

Learn more

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Times of India: US Finalises Alien Registration Rule: H-1B Holders Need Not Register AgainLearn more

Fragomen news

Fragomen and SICPA Launch a Global Strategic Joint Venture to Advance Global Digital Identity Solutions

Fragomen and SICPA announced the formation of a global joint venture to advance next-generation digital identity solutions for governments, enterprises and individuals.

Learn more

Media mentions

The PIE: Canada Fraud Case Exposes “Acute” Sector Integrity Issues

Partner Jack Kim discusses how fraud has shaped Canada's international student reforms and ongoing integrity efforts.

Learn more

Blog post

Skilled Worker Salary Changes: What Employers Need to Know

In this blog, Senior Associate Charlotte Roberts explains what these changes mean for employers, why salary discounts may no longer be a reliable long-term strategy and how early workforce planning can help businesses continue to access international talent while managing compliance and costs.

Learn more

Media mentions

Markt und Mittelstand: EU-Entsendung: Diese Fehler kosten Unternehmen bis zu 500.000 Euro

Senior Associate Isabel Schnitzler outlines the key compliance considerations for employers with employees working across the EU.

Learn more

Podcast

Reality Check Pt. 3: Immigration Law in Pop Culture

Associates Julia Manacher and Stephanie Weaver examine immigration issues emerging in a popular reality television series, including K-1 visa denials, consular non-reviewability, fraud findings and changing adjudication policies.

Learn more

Blog post

Separating Fact and Fiction: Debunking Myths in German Citizenship Law

Manager Dr. Adela Schmidt examines common misconceptions in German citizenship law, including birthright citizenship, dual citizenship, citizenship by descent and naturalization processing, and explains why eligibility often depends on specific legal requirements, timelines and documentation.

Learn more

Awards

Fragomen Professionals Named 2026 TLC Lions Human Awards Americas Finalists

Partner Audrea Golding, Senior Associate Kyle Sommer and Senior Talent Development Director Wendy Milici have been named finalists in the 2026 TLC Lions Human Awards Americas, recognizing their contributions to human-centered leadership, workplace culture and inclusion.

Learn more

Media mentions

Biometric Update: Fragomen and SICPA Form JV to Join Digital Identity Market With End-to-End Platform

Fragomen and SICPA have launched a global joint venture to develop an end-to-end digital identity platform that enables secure identity verification, document authentication and verifiable credential management.

Learn more

Media mentions

Times of India: Trump Administration Eyes Tighter H-1B, Green Card and Student Visa Rules; Indians Could Be Among Most Affected

Senior Counsel Mitch Wexler discusses how potential changes to H-1B visas, employment-based green cards and OPT could impact employers’ workforce planning and compliance obligations.

Learn more

Media mentions

World Business Travel Forum: Leaders in Motion - Middle East Mobility and Travel Resilience

In a Leaders in Motion interview with World Business Travel Forum, Partner Ali Haider and Nomadic CEO Carsten Østberg discuss recent travel and mobility developments across the Middle East and practical considerations for employers managing cross-border talent in the region.

Learn more

Media mentions

Global Mobility Lawyer: Dairy Industry Gains Clarity on H-2A Guest Worker Eligibility

Partner Rachel Beardsley explains how new DHS guidance clarifies that dairy employers may use the H-2A program when they can demonstrate a temporary or seasonal labor need.

Learn more

Media mentions

Times of India: US Finalises Alien Registration Rule: H-1B Holders Need Not Register AgainLearn more

Fragomen news

Fragomen and SICPA Launch a Global Strategic Joint Venture to Advance Global Digital Identity Solutions

Fragomen and SICPA announced the formation of a global joint venture to advance next-generation digital identity solutions for governments, enterprises and individuals.

Learn more
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Important Updates
Important Updates
July 17, 2026 | United StatesUnited States: H-1B Cap Is Reached for FY 2027
July 17, 2026 | ChadChad: Visa-Free Entry for African Nationals Forthcoming
July 17, 2026 | CroatiaCroatia: Wide-ranging Immigration Reforms, Adoption of Certain Recast Single Permit Directive Rules
July 17, 2026 | CanadaThe PIE: Canada Fraud Case Exposes “Acute” Sector Integrity Issues
July 17, 2026 | United KingdomUnited Kingdom: Draft Code on Expanded Right to Work Scheme Clarifies Employer Obligations
July 17, 2026 | United StatesUnited States: H-1B Cap Is Reached for FY 2027
July 17, 2026 | ChadChad: Visa-Free Entry for African Nationals Forthcoming
July 17, 2026 | CroatiaCroatia: Wide-ranging Immigration Reforms, Adoption of Certain Recast Single Permit Directive Rules
July 17, 2026 | CanadaThe PIE: Canada Fraud Case Exposes “Acute” Sector Integrity Issues
July 17, 2026 | United KingdomUnited Kingdom: Draft Code on Expanded Right to Work Scheme Clarifies Employer Obligations
July 17, 2026 | United StatesUnited States: H-1B Cap Is Reached for FY 2027
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