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

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Learn more

Media mentions

Personnel Today: Migration Committee Proposes to Cut 24 Occupations From New Shortage List

Partner Louise Haycock discussed the Migration Advisory Committee’s Temporary Shortage List recommendations and the need for clear workforce plans and transitional arrangements.

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In this blog, Director Ana Bessa Santos explores what Swiss authorities expect from employers when assessing work permit applications—including why a well-developed business plan, realistic growth projections and evidence of a genuine operational presence are critical to supporting both initial applications and future permit renewals.

Learn more

Media mentions

Personnel Today: Migration Committee Proposes to Cut 24 Occupations From New Shortage List

Partner Louise Haycock discussed the Migration Advisory Committee’s Temporary Shortage List recommendations and the need for clear workforce plans and transitional arrangements.

Learn more

Media mentions

Business Insider: 3 Lawyers React to Trump's New Limits on Student Visas

Counsel Brian Hunt discusses how proposed changes to F-1 student visas could create uncertainty for international students transitioning to the US workforce.

Learn more

Media mentions

Deutscher AnwaltSpiegel: Rechtliche Risiken bei Mitarbeitereinsätzen aus dem Ausland

Senior Manager Katharina Vorländer explains how employers and clients can reduce legal risks during cross-border employee assignments in Germany.

Learn more

Blog post

Mainland vs. Free Zone in the UAE: Choosing the Right Company Structure in 2026

Senior Manager Zak Hynes explores the key factors businesses should consider when establishing a presence in the UAE—from operating model and visa requirements to banking, office needs and long-term growth plans—in our new blog. The right structure is the one that best supports your business strategy, not simply the lowest upfront cost.

Learn more

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2026 Regional Immigration Overviews | #MobilityMinute

Partner Catherine Macris highlights key findings from Fragomen’s 2026 regional immigration overviews, including tighter compliance controls, digital border transformation and emerging pathways for global talent.

Learn more

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Partner Karolina Schiffter discusses how the EU's extension of temporary protection for Ukrainian citizens through 2028 will affect employers in Poland.

Learn more

Fragomen news

Fragomen's Immigration Guide for the UK Tech Sector

Fragomen’s "Immigration Guide for the UK Tech Sector" introduces visa options available for those working and recruiting in the tech sector.

Learn more

Blog post

The J-1 Research Scholar Visa: An Underutilized Pathway for Employers to Retain Global Research Talent

Center for Strategy and Applied Insights Senior Director Leah Rogal examines how employers can use the J-1 Research Scholar visa to retain eligible global research talent, support long-term research initiatives and strengthen workforce and immigration planning.

Learn more

Blog post

Twenty Years Forward: What the Middle East Reveals About the Future of Global Mobility

In this blog, Middle East and Africa Private Client Practice Director Nofi Mojidi-Bayna explores how evolving residency frameworks across the region are reshaping long-term mobility planning and examines the three global forces transforming immigration strategy for businesses, investors and internationally mobile families.

Learn more

Blog post

UK Launches Visa Fees Reimbursement Scheme for Scale Ups Hiring Global Talent

In this blog, Associate Halil Kaya outlines the UK Visa Fees Reimbursement Scheme for Scale Ups, including eligibility requirements, available funding and key considerations for high-growth businesses recruiting international talent.

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
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Important Updates
Important Updates
July 24, 2026 | United StatesUnited States: Federal Appeals Court Declines to Stay Lower Court Order Vacating $100,000 H-1B Fee
July 24, 2026 | 🌐Middle East - The Latest News on Mobility and Travel Considerations
July 24, 2026 | United KingdomPersonnel Today: Migration Committee Proposes to Cut 24 Occupations From New Shortage List
July 24, 2026 | Saudi ArabiaSaudi Arabia: New Payment Methods for GOSI Social Security Contributions
July 24, 2026 | Republic of Korea (South Korea)South Korea: Digital Nomad Visa Trial Program Introduced
July 24, 2026 | United StatesUnited States: Federal Appeals Court Declines to Stay Lower Court Order Vacating $100,000 H-1B Fee
July 24, 2026 | 🌐Middle East - The Latest News on Mobility and Travel Considerations
July 24, 2026 | United KingdomPersonnel Today: Migration Committee Proposes to Cut 24 Occupations From New Shortage List
July 24, 2026 | Saudi ArabiaSaudi Arabia: New Payment Methods for GOSI Social Security Contributions
July 24, 2026 | Republic of Korea (South Korea)South Korea: Digital Nomad Visa Trial Program Introduced
July 24, 2026 | United StatesUnited States: Federal Appeals Court Declines to Stay Lower Court Order Vacating $100,000 H-1B Fee
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