Mallory Tosch Hoggatt
Image of Mallory Tosch Hoggatt

Mallory Tosch Hoggatt

Partner

Mallory is the managing partner of A&O Shearman’s Houston office.

She litigates on behalf of global corporations and financial institutions in connection with mergers, acquisitions, divestitures and other complex commercial transactions, and advises during the course of transactions to ensure defensibility against deal disputes—including busted deals, stockholder suits, post-closing and earnout disputes, and regulatory inquiries—while enabling clients to achieve their desired outcomes.

Clients describe Mallory as "wicked smart and aggressive,” explaining that she is “responsive, easy to work with and produces excellent legal work.”

Mallory also defends companies and their boards in a range of industries who face bet-the-company derivative and securities litigation and significant commercial disputes, including bankruptcy litigation, breach of fiduciary duty, breach of contract, and liability management exercises. Mallory counsels multinational corporations in connection with both internal and regulatory investigations and enjoys collaborating with clients to identify and defend against potential risks before those risks materialize, remarking that she is, “very relatable and understands how we do things.” 

Expertise

Industries

Experience

Representative matters

M&A Litigation
  • A large multinational technology company in arbitration of post-closing dispute concerning earnout and ordinary-course covenants. 
  • Ardagh Metal Packaging S.A. in connection with litigation arising out of a deSPAC merger. 
  • Pattern Energy Group in litigation arising out of its acquisition by CPPIB. 
  • Intercontinental Exchange Inc. (ICE) in litigation arising out of its acquisition of Black Knight.
  • Microvast Holdings Inc. in litigation arising out of its deSPAC transaction with Tuscan. 
  • Liberty Global in connection with litigation relating to its acquisition of Sunrise. 
  • A large investment bank in litigation arising out of advisory services provided to the National Football League. 
  • A large investment bank in connection with a Special Litigation Committee investigation into defense advisory services to a client facing an activist investor campaign. 
  • A large investment bank in connection with the deSPAC of Alta Mesa. 
  • A midstream oil & gas company in a post-closing earnout dispute. 
  • A private capital investor in a brewing company in connection with a post-closing earnout dispute. 
  • A large investment bank in connection with litigation challenging a founder’s interests in a subsidiary. 
  • Raytheon in the United Technologies merger. 
  • Goldman Sachs in litigation arising out of the sale of Saks Fifth Avenue. 
  • LyondellBasell in the A. Schulman acquisition. 
  • Liberty Global in connection with litigation arising out of the Liberty Broadband acquisition of Charter Communications. 
  • Capital Square Partners in the Aegis/Startek acquisition. 
  • CVS in the Aetna acquisition. 
  • Altice in the Cablevision acquisition. 
  • Dassault in the Exa acquisition. 
  • WebMD Health Corporation in its acquisition by Internet Brands, a portfolio company of Kohlberg Kravis Roberts & Co. L.P. (KKR). 
  • Pall in its acquisition by Danaher 
  • Daimler AG in connection with various Chrysler-related post-demerger litigations and disputes. 
  • Huntsman Corp. in a merger dispute with Hexion Chemicals Corp. 
  • Merrill Lynch in connection with shareholder litigation arising out of its merger with Bank of America. 
  • BCE Inc. against former subsidiary of Teleglobe Inc. 
Securities-Related Litigation 
  • Dow Inc. in first-of-its-kind securities class action and derivative litigations arising out of disclosures concerning the impact of tariffs on its business and financial performance. 
  • Taro Pharmaceutical Industries and Sun Pharmaceutical Industries in securities class action litigation arising out of Sun's acquisition of Taro. 
  • Lumen Technologies in securities and derivative litigations challenging various disclosures made in securities filings. 
  • A multinational, publicly listed chemicals and energy company on disclosure obligations relating to GHG emissions reduction targets and potential liability arising out of failure to achieve those targets.  
  • A publicly traded hospitality company in a dispute with a former director concerning the exercise of warrants. 
  • Altice USA and related entities and individuals in securities litigation arising out of IPO and in connection with Section 16(b) claims. 
  • Jefferies in a securities litigation related to the deSPAC acquisition of Waitr Holdings, Inc. 
  • Orbital ATK in securities litigation arising out of financial restatement. 
  • LyondellBasell in connection with securities disclosures and an associate fee application dispute. 
  • Underwriting syndicates, including clients such as Bank of America, Citigroup, Merrill Lynch, Credit Suisse and dozens of others, in separate securities class actions arising out of stock offerings of companies such as ZTO Express and Arconic. 
  • Countrywide and related entities in ongoing institutional RMBS purchaser actions filed in state and federal courts across the United States by institutional plaintiffs such as federal home loan banks, mutual and hedge funds, insurance companies and regional banks. 
  • Barclays in the FHLBS RMBS litigation. 
  • Countrywide with respect to litigation concerning CDOs. 
  • Todd Newman, former portfolio manager at Diamondback Capital, in connection with the reversal of his insider trading conviction. 
  • White-Collar and Regulatory Investigations 
  • A large multinational pharmaceutical distributor in a special litigation committee investigation. 
  • A major international financial institution in an internal investigation into mutual fund investment irregularities at a Mexican subsidiary, including potential insider trading and related internal governance issues. 
  • An international engineering and construction company in a criminal investigation by the United States Department of Justice for possible FCPA violations. 
  • Former executives of the South American subsidiary of a multinational company in connection with an FCPA investigation and a potential criminal investigation by local authorities. 
  • Employee of foreign automotive manufacturer in connection with investigation by U.S. authorities into potential regulatory, criminal, and antitrust violations. 
Antitrust Litigation 
  • A financial institution in the Mexican Government Bonds antitrust class action. 
  • A defense intelligence contractor in a no-poach antitrust class action. 
  • A financial institution in the ISDAFIX antitrust class action. 
  • A financial institution in a class action asserting violations of the Commodity Exchange Act and antitrust laws related to Yen LIBOR and TIBOR. 
  • A major European cargo airline in a criminal price-fixing cartel investigation and the follow-on federal class action lawsuit and related opt-out actions alleging a conspiracy to fix the prices of air cargo. 
Additional Complex Commercial Experience
  • Hunkemöller International B.V. in one of the first European bondholder litigations arising out of an uptier financing transaction. 
  • A large private equity oil & gas investor in midstream assets in various commercial disputes, including strategic advisory work with portfolio companies and contractual disputes with LLC co-owners. 
  • EnCap Flatrock Midstream in an MLP dispute arising out of an attempted IPO. 
  • A startup behind-the-meter data center energy solutions company in dispute with co-founder.
  • A startup hydrogen company in a breach of contract litigation with a services provider. 
  • Citigroup in a class action concerning purported misconduct in Mexico. 
  • Shorenstein Properties in connection with a commercial property dispute. 
  • Deutsche Bank in a foreclosure litigation in connection with a distressed hotel property.

Published Work

  • Co-author, (2026) “Delaware Law Developments 2025-2026: DGCL Amendments, Constitutional Challenges, and the Post-SB21 Landscape”, The Review of Securities & Commodities Regulation 
  • Co-author, (2026) “Court of Chancery Imposes Sanctions for Spoliation of Signal Messages”, Harvard Law School Forum on Corporate Governance 
  • Co-author, (2026) “ Delaware Supreme Court Reverses Invalidation Of Stockholder Agreement, Finding Belated Facial Challenge Was Barred by Laches”, Harvard Law School Forum on Corporate Governance 
  • Featured in, (2026) “The Race for Corporate America”, The Los Angeles and San Francisco Daily Journal 
  • Featured in, (2025) “To Litigate or Legislate? The Texas Approach to Building Corporate Law”, The AmLaw Litigation Daily at LAW.com 
  • Co-author, (2024; 2025) “Securities Litigation: A Practitioner’s Guide”, Practising Law Institute 
  • Co-author, (2024) “The Evolution of Delaware Corporate Law: Finding Certainty in Uncertain Times”, Revue Trimestrielle de Droit Financier 
  • Co-author, (2024) “6 Focus Areas For Companies Managing The Risks Of AI Use”, Law360 
  • Co-author, (2023) “Delaware Court of Chancery Grants Plaintiff Attorney’s Fees Award Under Corporate Benefit Doctrine for Demand to SPAC Board Leading to Adjusted Voting Structure in Connection with Merger”, The M&A Lawyer 
  • Author, (2022) “Delaware Court of Chancery Finds Personal Jurisdiction Over LLC ‘Acting Manager’ in Post-Closing Investor Action Challenging Merger with SPAC”, The M&A Lawyer 
  • Author, (2022) “Delaware Supreme Court Reverses Dismissal of a Post-Merger Suit for Alleged Breach of Fiduciary Duty Related to Disclosures on Appraisal Rights”, The M&A Lawyer 
  • Author, (2022) “Finding That Allegedly Conflicted Acquisition Satisfied Entire Fairness Review, Delaware Court of Chancery Rejects Breach of Fiduciary Duty Claims”, The M&A Lawyer 
  • Author, (2022) “Delaware Court of Chancery Rejects Motion to Stay SPAC Breach of Fiduciary Duty Suit Pending Parallel Federal Securities Action”, The M&A Lawyer 
  • Co-author, (2019) “Considerations in Venture Capital and M&A Transactions in the AI Mobility Industry”, Global Legal Insights to: AI, Machine Learning & Big Data 2019 
  • Author, (2019) “Lorenzo v. SEC: Potential Implications for Private Rights of Action”, State Bar of Texas: The Newsletter of the Corporate Counsel Section

Speaking Engagements

  • Panelist, “The Devil (in the Details) Went Down to Georgia! Why Boilerplate Provisions in M&A Agreements Matter!” American Bar Association - Business Law Section, April 2026 
  • Panelist, “Trends in Delaware Law,” New York City Bar Association’s Securities Litigation & Enforcement Conference, February 2026 
  • Presenter, “When the Deal Goes Wrong,” Practical Law Institute’s Drafting and Negotiating Corporate Agreements Conference, January 2025 & 2026 
  • Presenter, “Practical Considerations and Implications of Generative AI,” The Center for American and International Law – Institute for Law and Technology, October 2024 
  • Presenter, “Who Is A Controller Under Delaware Law? It Depends,” Dallas Bar Association M&A Section, April 2024 
  • Presenter, “The Evolving Landscape of ESG Litigation,” Texas General Counsel Forum Virtual CLE, March 2024 
  • Presenter, “Anticipatory Reach: Leveraging the Broad Potential of Artificial Intelligence While Mitigating the Risks,” Texas Rural Water Association, Rural Water Conference, March 2024 
  • Co-Presenter, The Evolving Landscape of ESG Litigation, University of Texas School of Law/The Review of Litigation Symposium: The ESG Legal Landscape, February 2024 
  • Co-presenter, Social Media and AI – Ethical Guidelines for Lawyers, Texas General Counsel Forum, May 2023 
  • Panelist, Taking & Defending Powerful Depositions, The Rossdale Group, July 2020

Leadership Positions And Professional Affiliations

  • Board of Directors, French American Chamber of Commerce – Texas 
  • Board of Directors, American Association for the International Commission of Jurists 
  • Member, Texas State Bar Association 
  • Member, Houston Bar Association 
  • Member, New York State Bar Association 
  • Member, New York City Bar Association

Awards

  • Future Star, Texas, Benchmark Litigation, 2026
  • Recognized by Best Lawyers in America for Commercial Litigation, 2025
  • Band 2 in Securities Litigation – Texas, Chambers USA, 2025-2026
  • Band 3 in Securities Litigation – Texas, Chambers USA, 2022-2024
  • Next Generation Lawyer for M&A Litigation Defense, The Legal 500, 2017-2026
  • Top Ten Most Influential Securities Litigation Lawyers in Texas, Business Today, 2023

Qualifications

Admissions

Texas, 2021
New York, 2008

Courts

United States District Courts for the Southern and Eastern Districts of New York 

United States District Court for the Eastern District of Michigan 

United States Court of Appeals for the Second and Fifth Circuit

Academic

B.S., Political Science (with honors);

B.A., European Studies, Millsaps College, 2002 

J.D., Seton Hall University School of Law, 2007 

- Magna Cum Laude 

- Order of the Coif

Languages

French
Disclaimer
A&O Shearman was formed on May 1, 2024 by the combination of Shearman & Sterling LLP and Allen & Overy LLP and their respective affiliates (the legacy firms). Any matters referred to above may include matters undertaken by one or more of the legacy firms rather than A&O Shearman.