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

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

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

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In a new blog, UK Government Affairs Strategy Director Shuyeb Muquit examines what this direction could mean for employers, including why access to international talent may increasingly be considered alongside investment, productivity, innovation, regional growth and long-term workforce development.

Learn more

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Polish Citizenship by Descent: Finding Family Records and Navigating Polish Archives

Poland Immigration Strategy Director Tomasz Rogala and Senior Associate Tomasz Rdzanek explain how applicants pursuing Polish citizenship by descent can locate family records, navigate archives and obtain documentary evidence that can be used in citizenship proceedings.

Learn more
Generic Insights

Fragomen news

2026年10月 米国移民法ダイジェストLearn more

Awards

Fragomen Recognized in 2027 Best Law Firms® Rankings in the United States

Fragomen has been recognized in the 2027 edition of Best Law Firms®, earning a National Tier 1 ranking in Immigration Law and 16 regional rankings across the United States.

Learn more

Media mentions

Global Underwater Hub: The Specialist Skills Needed to Deliver Future Offshore Projects

Director Kelly Hardman explores how early UK immigration planning and investment in domestic skills can help offshore businesses access the specialist expertise needed to deliver future projects.

Learn more

Media mentions

SHRM: Why ‘Hush Trips’ Can Pose Big Risks for Employers and Workers

Senior Counsel Jo Antoons explains the immigration, social security, insurance, employment law and tax risks that undisclosed international remote work can create for employers.

Learn more

Media mentions

Times of India: Immigration After the Midterms: A New Congress, but Who Holds the Power?

Senior Counsel Mitch Wexler discusses the potential impact of the US midterm elections on immigration policy and the areas where bipartisan support could shape future developments.

Learn more

Blog post

UK Earned Settlement: When Immigration Status Becomes an Incentive for Growth and Compliance

In a new blog, UK Government Affairs Strategy Director Shuyeb Muquit examines what the framework could mean for employers, including potential impacts on sponsorship costs, retention planning, employee communications and support for internationally mobile workers and their families.

Learn more

Blog post

What the 2026 Midterm Election Results Mean for U.S. Business Immigration and Employers

In a new blog, Partner K. Edward Raleigh examines what the election results could mean for employers and where businesses should focus now, from immigration compliance and workforce planning to state response procedures and preparation for increased scrutiny.

Learn more

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The PIE: UK to Increase HPI Visa Cap and Expand Eligibility to 150 Universities

Manager Russell Hodges discusses how the HPI visa expansion could help UK employers attract global talent.

Learn more

Fragomen news

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Fragomen has opened new offices in Hanoi and Ho Chi Minh City, expanding its presence and immigration capabilities across Asia Pacific.

Learn more

Media mentions

Human Resources Director: Global Mobility Risk Can No Longer Be an HR Afterthought

Partner Jack Kim discusses how organizations can take a more strategic approach to global mobility through actionable intelligence, proactive workforce planning and preparation for geopolitical disruptions.

Learn more

Blog post

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In a new blog, UK Government Affairs Strategy Director Shuyeb Muquit examines what this direction could mean for employers, including why access to international talent may increasingly be considered alongside investment, productivity, innovation, regional growth and long-term workforce development.

Learn more
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Important Updates
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November 6, 2026 | Saudi ArabiaSaudi Arabia: Temporary Regularization Initiative for Certain Yemeni Nationals
November 6, 2026 | CanadaCanada: 2027–2029 Immigration Levels Plan Maintains Overall Targets and Adds Permanent Residence Spaces
November 6, 2026 | CanadaCanada: Longer Employment Duration and Expanded Access Under Temporary Foreign Worker Program Low-Wage Stream
November 6, 2026 | IrelandIreland: Employment Permits Portal Offline Following Unauthorized Activity
November 6, 2026 | Saudi ArabiaSaudi Arabia: Pre-Travel Registration Now Possible for Land Border Arrivals, with Process to Become Mandatory in 2027
November 6, 2026 | Saudi ArabiaSaudi Arabia: Temporary Regularization Initiative for Certain Yemeni Nationals
November 6, 2026 | CanadaCanada: 2027–2029 Immigration Levels Plan Maintains Overall Targets and Adds Permanent Residence Spaces
November 6, 2026 | CanadaCanada: Longer Employment Duration and Expanded Access Under Temporary Foreign Worker Program Low-Wage Stream
November 6, 2026 | IrelandIreland: Employment Permits Portal Offline Following Unauthorized Activity
November 6, 2026 | Saudi ArabiaSaudi Arabia: Pre-Travel Registration Now Possible for Land Border Arrivals, with Process to Become Mandatory in 2027
November 6, 2026 | Saudi ArabiaSaudi Arabia: Temporary Regularization Initiative for Certain Yemeni Nationals
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