Mario A. de Castro

Senior Counsel, Co-Chair of Tax & Private Wealth Section
blank image Mario A. de Castro

Mario A. de Castro

Senior Counsel, Co-Chair of Tax & Private Wealth Section
Washington T: 202.469.3236 F: 202.327.6151
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Mario A. de Castro

Mario A. de Castro

SENIOR COUNSEL, CO-CHAIR OF TAX & PRIVATE WEALTH SECTION
mdecastro@whitefordlaw.com
WASHINGTON
T: 202.469.3236
F: 202.327.6151
Biography
BIOGRAPHY
Mr. de Castro advises globally active enterprises and closely held family businesses on tax and related international business matters. His experience includes international tax planning and structuring, reorganizing and M&A planning, due diligence, supply chain planning, advising on tax and corporate compliance matters, and high-level corporate provision review. His industry experience spans private equity, real estate, technology and telecommunications, Fintech, bio-life, crypto-currency issuers, hospitality, defense and service companies. Mr. de Castro is a frequent speaker on cross-border business and transaction matters and is fluent in Spanish.
 

Memberships & Activities

  • Fellow: American College of Tax Counsel (ACTC)
  • Member: Federal Bar Association
  • Member: American Bar Association; Tax Section
  • Member: The Florida Bar; Tax Section, International Section, Real Property Section, and Trust and Estate Law Section
  • Member: International Fiscal Association 
  • Board Member & Treasurer: CODESPA America (2017-2021); Active Volunteer (2017-Present)
  • Coach & Volunteer: Central Loudoun Little League (2022-Present)

*Not admitted to practice in Washington, DC
  • Represented various globally active privately held middle-market foreign-based FIN-TECH companies on expansion into the U.S. and advised on debt and capitalization strategies.
  • Advised various middle market private equity groups with respect to U.S. outbound (foreign) acquisition and divestiture structuring, foreign entity rationalization, repatriation strategies, capitalization and debt structuring, and management of U.S. and foreign tax compliance and information reporting (including W-8 and FATCA considerations). 
  • Provided tax counsel to foreign (from Europe, Latin America, and the Middle East) multinational groups with U.S. and U.S. group controlled foreign operations on implementation, navigation, and compliance with 2017 U.S. Tax Cuts and Jobs Act (“TCJA”) (with respect to GILTI, FDII, and BEAT provisions), and structuring and management of intercompany payment flows.
  • Represented large and middle-market focused U.S. based engineering and technology companies as outside international tax and corporate counsel on foreign expansion matters into Canada, Mexico and Latin America, Africa, and Southeast Asia, due diligence considerations, and U.S. international tax and related regulatory compliance.
  • Advised Latin America based multinational agri-tech business on acquisition of U.S. target with foreign operations, advised on tax due diligence matters, and general inbound and outbound considerations. 
  • Served various U.S. and foreign energy, alternative energy, and related infrastructure enterprises with acquisition due diligence matters, and overall U.S. international tax matters involving corporate structuring, capitalization of operations, repatriation, organic and situational growth, and investment wind-up (in U.S. inbound context, counsel involved advising on FIRPTA considerations).
  • Served foreign middle-market banking and FIN-TECH enterprises as tax counsel on U.S. information reporting and FATCA compliance and implementation of internal compliance manuals.
  • Represented foreign investor groups with respect to structuring U.S. real estate specific funds, advised on U.S. inbound international considerations, including choice of entity, treaty analysis, repatriation strategies, capitalization versus debt considerations, FIRPTA, and due diligence matters.
  • Represented and counseled various publicly held, private equity-owned, and privately held government defense and other sector contractors and subcontractors re: taxation and exposure in foreign jurisdictions where services are performed (such as Europe, Asia-Pacifica, Latin America, Iraq, Afghanistan, UAE, and Kuwait); international structuring concerning same, provision (ASC 740/Fin 48) technical review of issues impacting such clients, and assist with tax risk mitigation and compliance considerations, and interpretation of applicable income tax treaties and/or Status of Forces Agreements (“SOFAs”).
  • Represented private equity group with planning and structuring of defense/Gov Con specific funds from a domestic and international tax perspective.
  • Served as tax counsel on technical matters for various privately held U.S. manufacturing clients with $200M plus in revenues expanding and building out contract manufacturing operations in Asia, management of supply-chain tax considerations, and intercompany transactions.
  • Counseled $500M Brazil-based biotech-focused investment fund with U.S. inbound structuring and restructuring considerations and ongoing investments in portfolio companies.
  • Represented Puerto Rican publicly traded company on restructuring and international tax assessment review technical matters concerning Latin America and Caribbean region operations.
  • Counseled gaming and technology public company on matters related to Latin America expansion, advised on U.S. and Latin America cross-border considerations.
  • Counseled closely held U.S. apparel company on restructuring of contract manufacturing and supply chain and distribution network in Asia Pacific area with ultimate sales to U.S. customers.
  • Served as co-international tax counsel on $700M plus international restructuring transaction and implementation for publicly traded bio-tech/pharmaceutical company with operations in Europe involving management of intangibles utilized in foreign markets and capitalization of operations.
  • Served various publicly traded companies (on NYSE and NASDAQ) in hospitality, telecommunications, and technology and defense sectors with planning and implementation internal corporate reorganizations involving subsidiaries in multiple Asian, European, and Latin America jurisdictions, management of intangibles, and implementation of internal treasury and financing structures.
INSIGHTS

Co-presenter: Mind Your Money! Tax Incentives, Business Opportunities, and Compliance Considerations for Expanding Abroad, U.S.-Caribbean Business Conference, September 2023

Co-presenter: The New Corporate Transparency Act in the United States, Pangea-Net's Annual Tax Practice Meeting, October 2022

Speaker: "Latin American and Other International Corporate and Fiscal Transparency Developments," Javeriana Univ. School of Law, Bogota, Columbia, October 2022

Speaker: "Regional Legislative Tax Trends in a Post COVID-19 Landscape," 2021 Americas Regional Conference, Crowe Global Live Webcast, August 2021

Speaker: "U.S. and Romanian Tax Considerations for Cross-Border Investments and the Mobile Workforce," Romanian-American Chamber of Commerce, March 2021

Speaker: "Tax Incentive Strategy for U.S. Exporters: Interest-Charge DISC, Impact of TCJA, and Possible Biden Tax Reform Impact," Lorman, March 2021

Speaker: "Overview of Choice of Entity Considerations and U.S. Income Tax Treaties," Lorman, July 2020

Contributor & Editor: Ch. 18 "Finance and Licensing Companies" (at p. 149-164), in Practical International Tax Planning for UK Businesses, Croner-i Ltd., December 2018

Speaker: "FATCA/Common Reporting Standard: The Road to Fiscal Transparency - the U.S. Perspective," Crowe Horwath International Regional Americas Meeting, San Jose, Costa Rica, May 2017

Speaker: "A Primer on Accounting Methods, Changes in Methods, and Elections for Companies with International Operations (& International Tax Legislative and Regulatory Updates)," Tax Executive Institute - Virginia Chapter, March 2017

ARTICLES

December 9, 2024

Client Alert: U.S. Government Appeals National Injunction Against Corporate Transparency Act

Following a Texas federal district court’s issuance of a nationwide injunction temporarily halting enforcement of the Corporate Transparency Act (“CTA”), the U.S. government has filed an appeal with the U.S. Court of Appeals for the Fifth Circuit, challenging the district court’s findings (found here). In response to both the national injunction and the appeal, the Financial Crimes Enforcement Network (“FinCEN”), the agency responsible for enforcing the CTA, issued guidance (found here) clarifying that reporting companies are not currently required to file beneficial ownership information (“BOI”) reports and will not face liability for noncompliance “while the preliminary injunction remains in effect.”
December 4, 2024

Client Alert: Federal Court Grants Nationwide Preliminary Injunction Against Corporate Transparency Act

On December 3, 2024, the U.S. District Court for the Eastern District of Texas, Texas Top Cop Shop, Inc. v. Merrick Garland (Civil Action No. 4:24-CV-478), issued a memorandum opinion and order granting a nationwide preliminary injunction against the enforcement of the Corporate Transparency Act (“CTA”) and its implementing regulations and staying the compliance deadline for reporting companies pending further order of the court.
April 1, 2024

Corporate Transparency Act Guidelines

The Corporate Transparency Act’s (the “CTA”) reporting requirements are effective as of January 1, 2024. The one-pager linked in this article provides information on reporting requirements and deadlines.
March 4, 2024

Client Alert: Corporate Transparency Act (CTA) Found Unconstitutional by Federal District Court

On March 1, 2024, the U.S. District Court for the Northern District of Alabama in National Small Business United et al.  v. Janet Yellen et. al., Case No. 5:22-cv-1448-LCB,  held the Corporate Transparency Act (the “CTA”) to be unconstitutional. In this surprising decision, U.S. District Court Judge Liles C. Burke ruled “The CTA is unconstitutional because it cannot be justified as exercise of Congress’ enumerated powers.”
January 2, 2024

Client Alert: Corporate Transparency Act Update: FinCEN Reporting and Compliance Begins in 2024

The Corporate Transparency Act’s (the “CTA”) reporting requirements are effective as of January 1, 2024. As a result, many companies in the United States will have to report information about their beneficial owners, i.e., the individuals who ultimately own or control the company. They will have to report the information to the Financial Crimes Enforcement Network (FinCEN), a bureau of the U.S. Department of the Treasury.
June 26, 2023

Client Alert: A Primer on the Corporate Transparency Act: Highlights of Additional Requirements to Conduct Business

What is the Corporate Transparency Act?

On January 1, 2021, heightened entity and beneficial ownership reporting arrived in the United States with the enactment of the Corporate Transparency Act (the “CTA”), part of the National Defense Authorization Act for Fiscal Year 2021. The policy behind the CTA is to strengthen reporting and transparency as to who the beneficial economic owners are of business enterprises doing business in the United States. Prior to the passage of the CTA, the United States was viewed by some in the international marketplace as a tax haven for those looking to create shell companies to hide their assets through the formation of business entities in jurisdictions like Delaware or Florida, for instance.
March 3, 2023

Client Alert: SCOTUS Holds in Favor of Taxpayer on Contested Issue of Foreign Bank Account (FBAR) Non-Willful Penalties

 FBARs in a Nutshell and the Concerns 

FBAR Requirements:  Pursuant to the U.S. Bank Secrecy Act (“BSA”) (31 U.S.C. § 5314 et seq.), U.S. persons, individuals and companies, are required on a calendar basis to report each year to the U.S. Treasury’s Financial Crimes Enforcement Network (FinCEN) all financial interests in and signature authority over foreign financial accounts on FinCen Form 114  Foreign Bank Account Reports (“FBARs”). The FBAR filing threshold is triggered upon having account assets exceeding $10,000 USD in the aggregate at any time during the calendar year. The deadline for filing FBARs is April 15 with an automatic extension to October 15 each year.
September 7, 2022

Client Alert: Inflation Reduction Act’s Renewable Energy Incentives to Embolden U.S. Energy Transition

The Inflation Reduction Act (the “Act”), signed into law on August 16, 2022, creates new opportunities for the renewable energy industry and is a welcome change in an industry accustomed to uncertainty regarding its primary financial incentives. The Act’s provisions modified many of the clean energy credit and incentive provisions of last year’s Build Back Better Act.  The Act earmarks $374 billion for decarbonization and modernization of U.S.  manufacturing in the renewable energy sector (the “Renewable Sector”).
August 10, 2022

Client Alert: Inflation Reduction Act Speeds through Senate – Key Takeaways

This week the Senate has advanced the landmark tax, climate, and healthcare bill known as the Inflation Reduction Act (H.R. 5376) (“IRA”) which will be considered by the House of Representatives in the coming days and, if passed, will arrive on President Biden’s desk for signature into law.

PRESENTATIONS

May 31, 2022 - News

International Tax Attorney Joins Whiteford

Whiteford Taylor & Preston announced today that Mario A. de Castro, an international tax attorney with over twenty years of experience on international, corporate, and tax matters, has joined the firm.