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

Explore more at Fragomen

Media mentions

Australian Broadcasting Corporation: Overnights

Senior Counsel Dr. Anna Boucher discusses Australia’s net migration figures and recent changes to the country’s migration policies.

Learn more

Blog post

Can International Graduates in the Netherlands Qualify for the 30% Ruling? Eligibility Rules Explained

Tiemen Peters, Silvia Norte Mercade and Soraya Driessen outline when international graduates who studied in the Netherlands may qualify for the 30% ruling and the key eligibility, timing and compliance considerations for graduates and employers.

Learn more

Blog post

The Narrowing Talent Pipeline: From International Student to Corporate America

Counsel Susan Steger discusses how recent immigration developments may affect the pathway from F-1 study and practical training through H-1B sponsorship and permanent residence for U.S. employers recruiting and retaining early-career international talent.

Learn more

Blog post

Right to Work Changes: What Do They Mean for Employers in Northern England?

Manager Ko Ito, Senior Immigration Consultant Danielle Barks, Associate Naureen Malik and Trainee Solicitor Amna Ali outline how the expanded UK Right to Work Scheme could affect employers in Northern England and the practical steps businesses can take ahead of the 1 October 2026 changes.

Learn more

Media mentions

Business Traveller: Six Months in, the EU’s Entry/Exit System Isn’t Working

Partner Christine Sullivan discusses the implementation of the EU’s Entry/Exit System (EES) across member states and at border crossing points.

Learn more

Blog post

Polish Citizenship by Descent: A Practical Guide for 2026

Poland Immigration Strategy Director Tomasz Rogala, Senior Associate Tomasz Rdzanek and Senior Immigration Consultant Paulina Fołta-Cisak discuss who may qualify for Polish citizenship by descent, how historical events can affect a claim and what applicants should expect from the 2026 confirmation process.

Learn more

Media mentions

ABC News: What Australia can learn from 165 years of migration data

Senior Counsel Anna Boucher is quoted in ABC News regarding Australia's migration debate and what more than 165 years of migration data reveals about long-term immigration trends.

Learn more

Blog post

Swiss Immigration Quotas 2026: Are Work Permit Quotas Likely to Run Out Before Year-End?

Senior Immigration Consultant Alessandra Rüede discusses Switzerland’s 2026 work permit quota utilisation and what current availability, canton-level allocation practices and processing considerations mean for employers planning international hiring and mobility.

Learn more

Blog post

From Investment to Merit: Malta’s Citizenship Reset

Director Isobel Neilson and Manager Sophie Jo Wasson discuss Malta’s shift from citizenship by investment to merit-based naturalisation and outline what may contribute to a compelling application based on exceptional merit and national interest.

Learn more

Fragomen news

Letter to ICE/Student and Exchange Visitor Program on Curricular Practical TrainingLearn more

Blog post

Right to Work Changes from 1 October 2026: Why Employers Need to Act Now

Partner Naomi Goldshtein discusses the UK Right to Work changes taking effect from 1 October 2026 and what employers should do now to strengthen identity verification, workforce oversight and compliance across direct and extended worker populations.

Learn more

Awards

Senior Associate Tuğba Özyakup Appointed to Dutch Bar Legislative Committee on Immigration Law

Senior Associate Tuğba Özyakup has been appointed to the Dutch Bar’s Legislative Committee on Immigration Law, where she will contribute input and advice on proposed and existing immigration legislation.

Learn more

Media mentions

Australian Broadcasting Corporation: Overnights

Senior Counsel Dr. Anna Boucher discusses Australia’s net migration figures and recent changes to the country’s migration policies.

Learn more

Blog post

Can International Graduates in the Netherlands Qualify for the 30% Ruling? Eligibility Rules Explained

Tiemen Peters, Silvia Norte Mercade and Soraya Driessen outline when international graduates who studied in the Netherlands may qualify for the 30% ruling and the key eligibility, timing and compliance considerations for graduates and employers.

Learn more

Blog post

The Narrowing Talent Pipeline: From International Student to Corporate America

Counsel Susan Steger discusses how recent immigration developments may affect the pathway from F-1 study and practical training through H-1B sponsorship and permanent residence for U.S. employers recruiting and retaining early-career international talent.

Learn more

Blog post

Right to Work Changes: What Do They Mean for Employers in Northern England?

Manager Ko Ito, Senior Immigration Consultant Danielle Barks, Associate Naureen Malik and Trainee Solicitor Amna Ali outline how the expanded UK Right to Work Scheme could affect employers in Northern England and the practical steps businesses can take ahead of the 1 October 2026 changes.

Learn more

Media mentions

Business Traveller: Six Months in, the EU’s Entry/Exit System Isn’t Working

Partner Christine Sullivan discusses the implementation of the EU’s Entry/Exit System (EES) across member states and at border crossing points.

Learn more

Blog post

Polish Citizenship by Descent: A Practical Guide for 2026

Poland Immigration Strategy Director Tomasz Rogala, Senior Associate Tomasz Rdzanek and Senior Immigration Consultant Paulina Fołta-Cisak discuss who may qualify for Polish citizenship by descent, how historical events can affect a claim and what applicants should expect from the 2026 confirmation process.

Learn more

Media mentions

ABC News: What Australia can learn from 165 years of migration data

Senior Counsel Anna Boucher is quoted in ABC News regarding Australia's migration debate and what more than 165 years of migration data reveals about long-term immigration trends.

Learn more

Blog post

Swiss Immigration Quotas 2026: Are Work Permit Quotas Likely to Run Out Before Year-End?

Senior Immigration Consultant Alessandra Rüede discusses Switzerland’s 2026 work permit quota utilisation and what current availability, canton-level allocation practices and processing considerations mean for employers planning international hiring and mobility.

Learn more

Blog post

From Investment to Merit: Malta’s Citizenship Reset

Director Isobel Neilson and Manager Sophie Jo Wasson discuss Malta’s shift from citizenship by investment to merit-based naturalisation and outline what may contribute to a compelling application based on exceptional merit and national interest.

Learn more

Fragomen news

Letter to ICE/Student and Exchange Visitor Program on Curricular Practical TrainingLearn more

Blog post

Right to Work Changes from 1 October 2026: Why Employers Need to Act Now

Partner Naomi Goldshtein discusses the UK Right to Work changes taking effect from 1 October 2026 and what employers should do now to strengthen identity verification, workforce oversight and compliance across direct and extended worker populations.

Learn more

Awards

Senior Associate Tuğba Özyakup Appointed to Dutch Bar Legislative Committee on Immigration Law

Senior Associate Tuğba Özyakup has been appointed to the Dutch Bar’s Legislative Committee on Immigration Law, where she will contribute input and advice on proposed and existing immigration legislation.

Learn more
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Important Updates
Important Updates
September 18, 2026 | United StatesUnited States: Starting October 1, State Department Will Expand Online Presence Review to TN, TD, and I Visa Applicants
September 18, 2026 | AustraliaAustralia: Further Migration Reforms to Reduce Net Overseas Migration Announced
September 18, 2026 | AustraliaAustralia: Skilled Visa Processing Priorities Revised
September 18, 2026 | AustraliaAustralian Broadcasting Corporation: Overnights
September 18, 2026 | ThailandThailand: Reduction in Visa-Exempt Stay Duration Forthcoming
September 18, 2026 | United StatesUnited States: Starting October 1, State Department Will Expand Online Presence Review to TN, TD, and I Visa Applicants
September 18, 2026 | AustraliaAustralia: Further Migration Reforms to Reduce Net Overseas Migration Announced
September 18, 2026 | AustraliaAustralia: Skilled Visa Processing Priorities Revised
September 18, 2026 | AustraliaAustralian Broadcasting Corporation: Overnights
September 18, 2026 | ThailandThailand: Reduction in Visa-Exempt Stay Duration Forthcoming
September 18, 2026 | United StatesUnited States: Starting October 1, State Department Will Expand Online Presence Review to TN, TD, and I Visa Applicants
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