Partner

Angela C. Zambrano

Commercial Litigation and Disputes
Energy
Insurance
Labor, Employment and Immigration

angela.zambrano@sidley.com

Dallas +1 214 981 3405

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ANGELA ZAMBRANO co-leads Sidley’s Dallas office and is a premier commercial litigator, having recently been named The American Lawyer’s “Litigator of the Week” based on her complete victory in a US$100 million earn out arbitration proceeding, shortlisted as the “Litigator of the Year” by IFLR’s Women in Business Law, and recognized in “Commercial Litigation” by Best Lawyers in America from 2016–2022. Based on her outstanding trial results and sage legal advice in the Boardroom, she is ranked by Chambers USA in Texas: Dallas, Fort Worth & Surrounds – Commercial Litigation from 2020–2023, one of only a few women so recognized in the state of Texas.

Angela co-leads the firm’s Commercial Litigation and Disputes group and leads the firm’s Dallas litigation group. The firm’s Dallas litigation group has received considerable recognition, including being ranked by Chambers USA and previously named “Litigation Department of the Year” by Texas Lawyer.

Angela has won many high profile cases in a wide variety of areas within commercial litigation, including partnership disputes, purchase price adjustments, indemnification disputes, and earn out arbitrations, fraud and breach of contract disputes, energy litigation, securities litigation, consumer class action litigation, class and collective action employment litigation, trade secret disputes, litigation against governmental entities, whistleblower-related litigation, data breach and privacy related investigations and litigation, commercial vendor disputes and litigation, and telecommunications litigation. She also has an active board of directors-level internal investigations practice, particularly with respect to accounting, privacy, whistleblower, and employment related matters. Her arbitration experience has earned her a spot on the American Arbitration Association’s Roster of Arbitrators.

Angela is also active in firm leadership and in the Dallas community. She serves as a member of Sidley’s Executive Committee and as a co-leader of Sidley’s women’s initiative. Angela previously served as the President of the Dallas Women Lawyer’s Association. She currently serves on the Executive Board of the Dedman School of Law, having previously served as an adjunct professor teaching pretrial procedure. D Magazine named Angela to its “Best Lawyers in Dallas” list (2023; 2016–2020), Benchmark Litigation has named her a “Litigation Star” in Texas for her work in Commercial Litigation and Insurance (2015–2024), and she was named “Commercial Arbitration Lawyer of the Year” by Women in Business Law America (2023). She has received the Outstanding Female Lawyer and Outstanding Board Member awards by the Dallas Women Lawyer’s Association, the Distinguished Alumni Award by SMU Women in Law, and named the 2016 Emerging Leader by the SMU Dedman School of Law.

Recent Experience

Currently representing an energy services company in which she successfully moved to dismiss all of an intervenor’s claims against her client;
Currently representing a publicly traded company in an action against the Federal Trade Commission (FTC) in which she successfully obtained dismissal with prejudice of the FTC’s two primary courts against her client;
Currently representing a publicly traded company in an alleged whistleblower claim in which she successfully transferred the case to the Northern District of Texas and compelled arbitration;
Currently representing a client in a False Claims Act matter in which she successfully moved to enjoin a former private equity partner from disclosing confidential information;
Successfully represented a chemical manufacturing company in trade secret litigation, including successfully obtaining preliminary injunctive relief and a temporary restraining order;
Represented a REIT as lead trial counsel in a final evidentiary hearing of an earn-out arbitration and obtained a complete victory for her client, including a multimillion-dollar counterclaim award;
Represented an energy company in a state court matter as lead counsel and successfully obtained a summary judgment of all claims against her client within six months of the case being filed;
Represented a publicly traded building products company in a US$100 million earn-out proceeding in which Sidley prevailed on all claims;
Represented a private equity client in the arbitration of an earn-out dispute relating to a healthcare company in which she obtained a complete victory for her client;
Successfully represented a publicly traded company in a California class action litigation related to consumer location services in which Sidley successfully moved to dismiss and compel arbitration of all claims;
Successfully defeated a preliminary injunction filed against a telecommunications company for failure to provide services during the pandemic;
Represented a publicly traded building products company in a group of securities class actions and derivative actions in which she successfully moved to transfer and dismiss;
Successfully represented a telecommunications company in a damages trial in which Sidley’s damages model was adopted by the Court;
Represented a retail client in multiple wage-and-hour collective actions in which Sidley successfully won motions to transfer and compel arbitration;
Successfully moved to compel arbitration of all claims by a vendor against her energy company client;
Represented an energy company in an arbitration relating to indemnification claims;
Represented a client relating to multiple inquiries from DOJ, USDA and TDA relating to government contracts issues;
Represented a mortgage company in a class action relating to the purchase of assets from the government that she successfully resolved;
Represented a mortgage company in multiple misappropriation of trade secrets and employee-related disputes, including successfully compelling dispute to arbitration;
Successfully represented an energy company, healthcare companies, and a telecommunications company in multiple FLSA and wage payment matters;
Represented a private equity client in an arbitration where she obtained several early favorable rulings and ultimately a favorable settlement in which the client was able to recoup its entire investment in a media company;
Represented several insurance-related entities in an action involving allegations of fraud and breach of contract in which she obtained a dismissal with prejudice for all of her clients;
Represented a pharmaceutical company in an arbitration with its vendor in which she obtained interim measures from the arbitrator shortly after the arbitrator was appointed, leading to a favorable settlement for her client;
Successfully represented an entertainment company in connection with class action consumer disputes related to the company’s rewards program and gift cards;
Represented an energy company in a trespass dispute in which she successfully defeated a plea to the jurisdiction and motion for protection; and
Advised on multiple data breach and privacy-related investigations and related litigation.

Experience

Prior to joining Sidley, Angela was a partner at another Am Law Top 10 firm where she successfully represented numerous clients.

Phyllis Schultz v. Ability Insurance Company, et al.; Hull, et al. v. Ability Insurance Company — National coordinating counsel for defendants in multiple cases in U.S. federal courts in Montana, South Dakota, Iowa, and Washington brought by long-term care policyholders. Hired post-trial, she obtained a significant reduction in the damages verdict awarded in favor of a long-term care policyholder in Montana federal court;
American Airlines Inc. v. Sabre Inc., et al.; American Airlines Inc. v. Travelport Ltd., et al. — Representation of plaintiff in antitrust litigation in Texas state and federal court alleging anticompetitive conduct by leading providers of global distribution systems;
General Motors — Representation of debtor in the historic, multinational automotive restructuring. Responsible for expunction or resolution of all class action claims against debtor. Also formed and administered mediation program for debtor whereby more than US$11 billion in claims have been resolved;
Trump Entertainment Resorts, Inc. — Representation of Trump Entertainment Resorts and certain of its subsidiaries (one of the largest casino operators/owners in Atlantic City, New Jersey) in the reorganization of their business under Chapter 11 of the Bankruptcy Code. The reorganization included a US$225 million equity infusion by certain creditors, the restructuring of the company’s first-lien credit facility through a US$125 million cash payment and the issuance of new first-lien term notes, the cancellation of US$1.25 billion of second-lien debt and all existing publicly held common stock, and the execution of a new trademark agreement with Donald J. Trump in exchange for new common stock and warrants. The company’s Chapter 11 plan became effective after a hotly contested, nine-day confirmation hearing in which Angela served as trial counsel;
Hawkeye Renewable — Representation of debtors in connection with reorganization case, including the trial of the objection of the second-lien lender group. Angela served as trial counsel at the confirmation;
SemGroup, L.P. — Representation of debtors in connection with internal investigation into cause of debtors’ trading losses and in connection with various governmental investigations;
HealthMarkets, Inc. — Representation of HealthMarkets, Inc. and its subsidiaries in consumer fraud action filed by Attorney General of Massachusetts;
Enron Power Marketing, Inc. v. Virginia Electric and Power Co., d/b/a Dominion Virginia Power — Representation of Enron in an adversary proceeding seeking recovery for breach of energy contract;
Highland Crusader Offshore Partners, L.P., et al. v. Motient Corporation — Representation of defendant in state court lawsuit seeking rescission of stock purchase;
Representation of Special Committee of the board of directors of a publicly traded retail company investigating historical stock option granting practices;
UICI, The MEGA Life and Health Insurance Company, and Mid-West Life Insurance Company of Tennessee — National coordinating counsel for multidistrict litigation case In re UICI “Association Group” Insurance Litigation, Docket No. 1578 (Judicial Panel on Multidistrict Litigation, D.C.) and over 30 individual and class action cases in multiple states, including Alabama, Arkansas, California, Colorado, Georgia, Idaho, Mississippi, New Mexico, North Carolina, Oklahoma, and Texas;
In re UICI Sec. Litig. (N.D. Tex.) — Counsel for HealthMarkets, Inc. (f/k/a UICI) and former officers and directors in federal shareholder class action, asserting claims under Sections 10(b) and 20(a) of the Securities Exchange Act of 1934;
Richard Schappel v. UICI, et al. — Counsel for the corporate defendant, UICI, in Texas state court shareholders’ derivative case. Following an investigation by independent counsel, plaintiff’s request for attorneys’ fees was tried to the court in a two-day bench trial. The court awarded plaintiff a fraction of the requested fee amount after the trial. Angela served as trial counsel in the matter;
Stoneville Pedigreed Seed Company v. House of Agriculture Spirou A.E.B.E. — Counsel in arbitration before the American Arbitration Association, Geneva, Switzerland, concerning termination of Greek distributorship agreement, including defense of opponent’s US$1.25 billion counterclaim. Following two evidentiary hearings and argument, Tribunal ruled that the client had properly terminated the agreement. Angela served as trial counsel at the hearings;
In re Footstar, Inc., et al. — Counsel in bankruptcy litigation against Kmart, Inc.;
Mitsumi Electric Co., Ltd. v. Swan Magnetics, Inc., et al. — Counsel for Mitsumi in a misappropriation of trade secrets case. Case settled favorably for Mitsumi after plaintiff’s case was presented at trial;
American Credit Educators LLC and American Fair Credit Association, Inc. v. United Credit National Bank, et al.; UICI, et al. v. Phillip A. Gray, et al.; UICI, et al. v. Dennis M. Weseloh; William K. Lester, on Behalf of United Credit National Bank v. John E. Allen, et al. — Counsel for UICI in federal and state court litigation involving its sub-prime credit card business. Obtained various favorable pre-trial rulings and settlement;
Silver v. UICI, et al. — Counsel for defendant in federal class action securities action; and
IPOC International Growth Fund, Ltd. v. TMI, et al. — Worked with local counsel in the British Virgin Islands to successfully dissolve Mareva injunction.

Advisory Board Member and Former President, Dallas Women Lawyers Association
Executive Board Member, SMU Dedman School of Law
American Arbitration Association, Roster of Arbitrators
Board Member, Texas Appleseed
Leadership Dallas (2019 Class)
Litigation Counsel of America, The Trial Lawyer Honorary Society
Institute for Energy Law, Advisory Board
American Bar Association
Texas Bar Association
New York Bar Association
National Association of Women Lawyers

Credentials

Admissions & Certifications

U.S. Court of Appeals, 9th Circuit
U.S. Court of Appeals, 10th Circuit
U.S. District Court, E.D. of Texas
U.S. District Court, W.D. of Texas
U.S. District Court, N.D. of Texas
New York
Texas

Angela C. Zambrano

Credentials

Admissions & Certifications

Education

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