Important Updates
Important Updates
April 30, 2026 | 🌐Middle East - The Latest News on Mobility and Travel Considerations
May 1, 2026 | United StatesUnited States: Federal District Court Stays Termination of Yemen TPS
May 1, 2026 | United StatesUnited States: Summer 2026 Travel Considerations for Foreign Nationals
April 30, 2026 | Hong Kong SARHong Kong SAR: Earlier Extension Filing Announced
April 30, 2026 | IndonesiaIndonesia: New Password Rule Could Delay Applications if Email Addresses are Invalid or Inaccessible
April 30, 2026 | 🌐Middle East - The Latest News on Mobility and Travel Considerations
May 1, 2026 | United StatesUnited States: Federal District Court Stays Termination of Yemen TPS
May 1, 2026 | United StatesUnited States: Summer 2026 Travel Considerations for Foreign Nationals
April 30, 2026 | Hong Kong SARHong Kong SAR: Earlier Extension Filing Announced
April 30, 2026 | IndonesiaIndonesia: New Password Rule Could Delay Applications if Email Addresses are Invalid or Inaccessible
April 30, 2026 | 🌐Middle East - The Latest News on Mobility and Travel Considerations
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William Diaz

Senior Manager

William Diaz

William Diaz
William Diaz
  • People

Senior Manager

William Diaz

Country / Territory

  • United KingdomUnited Kingdom

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  • English

Contact information

Email

[email protected]

T:+44 (0)207 090 9272

F:+44 (0)207 090 9101

Fragomen in London

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1st Floor, 95 Gresham St,

London EC2V 7NA

United Kingdom

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Email

[email protected]

T:+44 (0)207 090 9272

F:+44 (0)207 090 9101

Fragomen in 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

Fragomen in London

Fragomen LLP

1st Floor, 95 Gresham St,

London EC2V 7NA

United Kingdom

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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

Fragomen in 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

Fragomen in 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

Fragomen in 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

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EB-5 I-526E Request For Evidence Trends: Loans and Property Sales

Senior Associate Tracey Kimberly explores the recent increase in RFEs for EB‑5 I‑526E petitions, highlighting heightened USCIS scrutiny of source-of-funds documentation—particularly in cases involving loan-based investments and property sale proceeds.

Learn more

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The Nordic Immigration Paradox: Why Digital Efficiency Still Creates Compliance Risk

Director Audrey Morew examines how Nordic immigration systems, while increasingly digital and efficient, can embed compliance risk earlier in the process—placing greater responsibility on employers to ensure data accuracy, internal controls and long‑term compliance from the outset.

Learn more

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Senior Counsel Jo Antoons, Senior Immigration Managers Manuela Birsan and Andreia Ghimis, Senior Manager Wout Van Doren, Associate Pauline Chomel and Immigration Supervisor Elisabeth Kamm contributed to the European Migration Network (EMN) Belgium report "Labour Migration in Times of Labour Shortages in Belgium."

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Learn more

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Ireland Immigrant Investor Programme: Is the “Golden Visa” Route Now Closed?

Senior Manager Samantha Arnold examines the closure of Ireland’s Immigrant Investor Programme and outlines the limited remaining options for high net worth individuals seeking Irish residence through approved investment and charitable donation routes.

Learn more

Video

May 2026 Visa Bulletin | #MobilityMinute

Partner Melissa Vasquez-Myers highlights key updates from the May 2026 Visa Bulletin, including a pause in employment-based advancement, continued movement in family-based categories and a warning of potential retrogression later this fiscal year.

Learn more

Awards

Citywealth Leaders List: Top 30 Immigration Advisors 2026 Recognises Four Fragomen Professionals

Partners Parisa Karaahmet, Raquel Liberman and Julia Onslow-Cole and Practice Leader Olga Nechita are recognised in Citywealth’s Top 30 Immigration Advisors 2026 for their leadership in advising high-net-worth individuals and families on global mobility and cross-border planning.

Learn more

Work authorization

EB-5 I-526E Request For Evidence Trends: Loans and Property Sales

Senior Associate Tracey Kimberly explores the recent increase in RFEs for EB‑5 I‑526E petitions, highlighting heightened USCIS scrutiny of source-of-funds documentation—particularly in cases involving loan-based investments and property sale proceeds.

Learn more

Work authorization

The Nordic Immigration Paradox: Why Digital Efficiency Still Creates Compliance Risk

Director Audrey Morew examines how Nordic immigration systems, while increasingly digital and efficient, can embed compliance risk earlier in the process—placing greater responsibility on employers to ensure data accuracy, internal controls and long‑term compliance from the outset.

Learn more

Work authorization

Canada FIFA World Cup 2026 Visa & Entry Requirements

Partner Rick Lamanna outlines Canada’s entry requirements for the FIFA World Cup 2026, highlighting visa and eTA processes, border expectations and special measures for participants to help travelers prepare for seamless entry during the tournament.

Learn more

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The PIE: Relief for Some OPT Applicants in “Immigration Limbo”

Partners Aaron Blumberg and Daniel Pierce discuss how a US pause on processing certain work permit applications including OPT creates uncertainty for international students and employers while early court rulings offer limited case-specific relief.

Learn more

Fragomen news

European Migration Network (EMN) Belgium Report: Labour Migration in Times of Labour Shortages in Belgium

Senior Counsel Jo Antoons, Senior Immigration Managers Manuela Birsan and Andreia Ghimis, Senior Manager Wout Van Doren, Associate Pauline Chomel and Immigration Supervisor Elisabeth Kamm contributed to the European Migration Network (EMN) Belgium report "Labour Migration in Times of Labour Shortages in Belgium."

Learn more

Work authorization

From Investment to EU Residence: Why Italy’s Investor Visa is Gaining Momentum

Manager Pierangelo D'Errico explores how Italy’s Investor Visa is emerging as a strategic alternative to diminishing EU golden visa programmes, offering high‑net‑worth individuals flexible residence rights, deferred investment timing, Schengen access and a structured—though not accelerated—pathway to long‑term EU residence.

Learn more

Media mentions

The New York Times: Have a Canadian Great-Great Grandparent? It Could Make You Canadian.

Partner Rick Lamanna discusses Canada’s expanded citizenship by descent rules extending eligibility to potentially millions of people worldwide with only distant ancestral ties.

Learn more

Awards

Fragomen Features in Ibec’s Top 100 Companies Leading in Wellbeing Index 2026

Fragomen is recognised in Ibec’s Top 100 Companies Leading in Wellbeing Index 2026, highlighting its commitment to employee wellbeing and a supportive workplace culture.

Learn more

Work authorization

The UK Global Talent Visa as a Flexible Residence Option for High-Net-Worth Individuals

Senior Manager Alexander Hood and Senior Associate Lara Hannaway outline how the UK Global Talent visa is increasingly being used by internationally mobile individuals as a flexible UK residence option, examining who the route is designed for, the endorsement process and the sectors currently covered, including the new design route launching in July 2026.

Learn more

Work authorization

Ireland Immigrant Investor Programme: Is the “Golden Visa” Route Now Closed?

Senior Manager Samantha Arnold examines the closure of Ireland’s Immigrant Investor Programme and outlines the limited remaining options for high net worth individuals seeking Irish residence through approved investment and charitable donation routes.

Learn more

Video

May 2026 Visa Bulletin | #MobilityMinute

Partner Melissa Vasquez-Myers highlights key updates from the May 2026 Visa Bulletin, including a pause in employment-based advancement, continued movement in family-based categories and a warning of potential retrogression later this fiscal year.

Learn more

Awards

Citywealth Leaders List: Top 30 Immigration Advisors 2026 Recognises Four Fragomen Professionals

Partners Parisa Karaahmet, Raquel Liberman and Julia Onslow-Cole and Practice Leader Olga Nechita are recognised in Citywealth’s Top 30 Immigration Advisors 2026 for their leadership in advising high-net-worth individuals and families on global mobility and cross-border planning.

Learn more

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